Back out 530555a2d6d4 (bug 1162064) for debug b2g emulator assertions and failure to thrive

CLOSED TREE

docshell/base/nsDocShell.cpp

@@ -13858,14 +13858,7 @@ nsDocShell::GetAppManifestURL(nsAString& aAppManifestURL)
 NS_IMETHODIMP
 nsDocShell::GetAsyncPanZoomEnabled(bool* aOut)
 {
-  if (nsIPresShell* presShell = GetPresShell()) {
+  *aOut = Preferences::GetBool("layers.async-pan-zoom.enabled", false);
-    if (layers::LayerManager* lm = presShell->GetLayerManager()) {
-      *aOut = lm->AsyncPanZoomEnabled();
-      return NS_OK;
-    }
-  }
-
-  *aOut = false;
   return NS_OK;
 }
 

dom/base/nsDOMWindowUtils.cpp

@@ -375,12 +375,9 @@ nsDOMWindowUtils::SetDisplayPortForElement(float aXPx, float aYPx,
                        new DisplayPortPropertyData(displayport, aPriority),
                        nsINode::DeleteProperty<DisplayPortPropertyData>);
 
-  if (gfxPrefs::LayoutUseContainersForRootFrames()) {
+  if (nsLayoutUtils::UsesAsyncScrolling() && gfxPrefs::LayoutUseContainersForRootFrames()) {
     nsIFrame* rootScrollFrame = presShell->GetRootScrollFrame();
-    if (rootScrollFrame &&
+    if (rootScrollFrame && content == rootScrollFrame->GetContent()) {
-        content == rootScrollFrame->GetContent() &&
-        nsLayoutUtils::UsesAsyncScrolling(rootScrollFrame))
-    {
       // We are setting a root displayport for a document.
       // The pres shell needs a special flag set.
       presShell->SetIgnoreViewportScrolling(true);
@@ -861,7 +858,7 @@ nsDOMWindowUtils::SendWheelEvent(float aX,
 
   widget->DispatchAPZAwareEvent(&wheelEvent);
 
-  if (widget->AsyncPanZoomEnabled()) {
+  if (gfxPrefs::AsyncPanZoomEnabled()) {
     // Computing overflow deltas is not compatible with APZ, so if APZ is
     // enabled, we skip testing it.
     return NS_OK;

dom/ipc/PBrowser.ipdl

@@ -515,8 +515,7 @@ parent:
 
     sync GetRenderFrameInfo(PRenderFrame aRenderFrame)
         returns (TextureFactoryIdentifier textureFactoryIdentifier,
-                 uint64_t layersId,
+                 uint64_t layersId);
-                 bool asyncPanZoomEnabled);
 
     /**
      * Sent by the child to the parent to inform it that an update to the
@@ -546,8 +545,7 @@ child:
          TextureFactoryIdentifier textureFactoryIdentifier,
          uint64_t layersId,
          nullable PRenderFrame renderFrame,
-         bool parentIsActive,
+         bool parentIsActive);
-         bool asyncPanZoomEnabled);
 
     LoadURL(nsCString uri, BrowserConfiguration config);
 

dom/ipc/TabChild.cpp

@@ -268,8 +268,7 @@ CSSToParentLayerScale ConvertScaleForRoot(CSSToScreenScale aScale) {
 bool
 TabChildBase::HandlePossibleViewportChange(const ScreenIntSize& aOldScreenSize)
 {
-  nsIWidget* widget = WebWidget();
+  if (!gfxPrefs::AsyncPanZoomEnabled()) {
-  if (!widget || !widget->AsyncPanZoomEnabled()) {
     return false;
   }
 
@@ -876,7 +875,6 @@ TabChild::TabChild(nsIContentChild* aManager,
   , mDefaultScale(0)
   , mIPCOpen(true)
   , mParentIsActive(false)
-  , mAsyncPanZoomEnabled(false)
 {
   // preloaded TabChild should not be added to child map
   if (mUniqueId) {
@@ -923,7 +921,7 @@ TabChild::Observe(nsISupports *aSubject,
       }
     }
   } else if (!strcmp(aTopic, BEFORE_FIRST_PAINT)) {
-    if (AsyncPanZoomEnabled()) {
+    if (gfxPrefs::AsyncPanZoomEnabled()) {
       nsCOMPtr<nsIDocument> subject(do_QueryInterface(aSubject));
       nsCOMPtr<nsIDocument> doc(GetDocument());
 
@@ -981,7 +979,7 @@ TabChild::OnLocationChange(nsIWebProgress* aWebProgress,
                            nsIURI *aLocation,
                            uint32_t aFlags)
 {
-  if (!AsyncPanZoomEnabled()) {
+  if (!gfxPrefs::AsyncPanZoomEnabled()) {
     return NS_OK;
   }
 
@@ -1539,11 +1537,9 @@ TabChild::ProvideWindowCommon(nsIDOMWindow* aOpener,
   TextureFactoryIdentifier textureFactoryIdentifier;
   uint64_t layersId = 0;
   PRenderFrameChild* renderFrame = newChild->SendPRenderFrameConstructor();
-  bool asyncPanZoomEnabled = false;
   newChild->SendGetRenderFrameInfo(renderFrame,
                                    &textureFactoryIdentifier,
-                                   &layersId,
+                                   &layersId);
-                                   &asyncPanZoomEnabled);
   if (layersId == 0) { // if renderFrame is invalid.
     PRenderFrameChild::Send__delete__(renderFrame);
     renderFrame = nullptr;
@@ -1551,8 +1547,7 @@ TabChild::ProvideWindowCommon(nsIDOMWindow* aOpener,
 
   // Unfortunately we don't get a window unless we've shown the frame.  That's
   // pretty bogus; see bug 763602.
-  newChild->DoFakeShow(textureFactoryIdentifier, layersId, renderFrame,
+  newChild->DoFakeShow(textureFactoryIdentifier, layersId, renderFrame);
-                       asyncPanZoomEnabled);
 
   for (size_t i = 0; i < frameScripts.Length(); i++) {
     FrameScriptInfo& info = frameScripts[i];
@@ -1880,12 +1875,11 @@ TabChild::CancelCachedFileDescriptorCallback(
 void
 TabChild::DoFakeShow(const TextureFactoryIdentifier& aTextureFactoryIdentifier,
                      const uint64_t& aLayersId,
-                     PRenderFrameChild* aRenderFrame,
+                     PRenderFrameChild* aRenderFrame)
-                     bool aAsyncPanZoomEnabled)
 {
   ShowInfo info(EmptyString(), false, false, 0, 0);
   RecvShow(ScreenIntSize(0, 0), info, aTextureFactoryIdentifier,
-           aLayersId, aRenderFrame, mParentIsActive, aAsyncPanZoomEnabled);
+           aLayersId, aRenderFrame, mParentIsActive);
   mDidFakeShow = true;
 }
 
@@ -1987,8 +1981,7 @@ TabChild::RecvShow(const ScreenIntSize& aSize,
                    const TextureFactoryIdentifier& aTextureFactoryIdentifier,
                    const uint64_t& aLayersId,
                    PRenderFrameChild* aRenderFrame,
-                   const bool& aParentIsActive,
+                   const bool& aParentIsActive)
-                   const bool& aAsyncPanZoomEnabled)
 {
     MOZ_ASSERT((!mDidFakeShow && aRenderFrame) || (mDidFakeShow && !aRenderFrame));
 
@@ -2021,8 +2014,6 @@ TabChild::RecvShow(const ScreenIntSize& aSize,
     bool res = InitTabChildGlobal();
     ApplyShowInfo(aInfo);
     RecvParentActivated(aParentIsActive);
-
-    mAsyncPanZoomEnabled = aAsyncPanZoomEnabled;
     return res;
 }
 
@@ -2208,7 +2199,7 @@ TabChild::RecvMouseWheelEvent(const WidgetWheelEvent& aEvent,
                               const ScrollableLayerGuid& aGuid,
                               const uint64_t& aInputBlockId)
 {
-  if (AsyncPanZoomEnabled()) {
+  if (gfxPrefs::AsyncPanZoomEnabled()) {
     nsCOMPtr<nsIDocument> document(GetDocument());
     APZCCallbackHelper::SendSetTargetAPZCNotification(WebWidget(), document, aEvent, aGuid,
         aInputBlockId);
@@ -2218,7 +2209,7 @@ TabChild::RecvMouseWheelEvent(const WidgetWheelEvent& aEvent,
   event.widget = mWidget;
   APZCCallbackHelper::DispatchWidgetEvent(event);
 
-  if (AsyncPanZoomEnabled()) {
+  if (gfxPrefs::AsyncPanZoomEnabled()) {
     mAPZEventState->ProcessWheelEvent(event, aGuid, aInputBlockId);
   }
   return true;
@@ -2400,7 +2391,7 @@ TabChild::RecvRealTouchEvent(const WidgetTouchEvent& aEvent,
   APZCCallbackHelper::ApplyCallbackTransform(localEvent, aGuid,
       mWidget->GetDefaultScale(), GetPresShellResolution());
 
-  if (localEvent.message == NS_TOUCH_START && AsyncPanZoomEnabled()) {
+  if (localEvent.message == NS_TOUCH_START && gfxPrefs::AsyncPanZoomEnabled()) {
     if (gfxPrefs::TouchActionEnabled()) {
       APZCCallbackHelper::SendSetAllowedTouchBehaviorNotification(WebWidget(),
           localEvent, aInputBlockId, mSetAllowedTouchBehaviorCallback);
@@ -2413,7 +2404,7 @@ TabChild::RecvRealTouchEvent(const WidgetTouchEvent& aEvent,
   // Dispatch event to content (potentially a long-running operation)
   nsEventStatus status = APZCCallbackHelper::DispatchWidgetEvent(localEvent);
 
-  if (!AsyncPanZoomEnabled()) {
+  if (!gfxPrefs::AsyncPanZoomEnabled()) {
     UpdateTapState(localEvent, status);
     return true;
   }

dom/ipc/TabChild.h

@@ -319,8 +319,7 @@ public:
                           const TextureFactoryIdentifier& aTextureFactoryIdentifier,
                           const uint64_t& aLayersId,
                           PRenderFrameChild* aRenderFrame,
-                          const bool& aParentIsActive,
+                          const bool& aParentIsActive) override;
-                          const bool& aAsyncPanZoomEnabled) override;
     virtual bool RecvUpdateDimensions(const nsIntRect& rect,
                                       const ScreenIntSize& size,
                                       const ScreenOrientation& orientation,
@@ -505,7 +504,6 @@ public:
     {
       return mParentIsActive;
     }
-    bool AsyncPanZoomEnabled() { return mAsyncPanZoomEnabled; }
 
 protected:
     virtual ~TabChild();
@@ -562,8 +560,7 @@ private:
     // Call RecvShow(nsIntSize(0, 0)) and block future calls to RecvShow().
     void DoFakeShow(const TextureFactoryIdentifier& aTextureFactoryIdentifier,
                     const uint64_t& aLayersId,
-                    PRenderFrameChild* aRenderFrame,
+                    PRenderFrameChild* aRenderFrame);
-                    bool aAsyncPanZoomEnabled);
 
     void ApplyShowInfo(const ShowInfo& aInfo);
 
@@ -643,7 +640,6 @@ private:
     double mDefaultScale;
     bool mIPCOpen;
     bool mParentIsActive;
-    bool mAsyncPanZoomEnabled;
 
     DISALLOW_EVIL_CONSTRUCTORS(TabChild);
 };

dom/ipc/TabParent.cpp

@@ -888,8 +888,7 @@ TabParent::Show(const ScreenIntSize& size, bool aParentIsActive)
     }
 
     unused << SendShow(size, info, textureFactoryIdentifier,
-                       layersId, renderFrame, aParentIsActive,
+                       layersId, renderFrame, aParentIsActive);
-                       AsyncPanZoomEnabled());
 }
 
 bool
@@ -2649,15 +2648,12 @@ TabParent::DeallocPRenderFrameParent(PRenderFrameParent* aFrame)
 bool
 TabParent::RecvGetRenderFrameInfo(PRenderFrameParent* aRenderFrame,
                                   TextureFactoryIdentifier* aTextureFactoryIdentifier,
-                                  uint64_t* aLayersId,
+                                  uint64_t* aLayersId)
-                                  bool* aAsyncPanZoomEnabled)
 {
   RenderFrameParent* renderFrame = static_cast<RenderFrameParent*>(aRenderFrame);
   renderFrame->GetTextureFactoryIdentifier(aTextureFactoryIdentifier);
   *aLayersId = renderFrame->GetLayersId();
 
-  *aAsyncPanZoomEnabled = AsyncPanZoomEnabled();
-
   if (mNeedLayerTreeReadyNotification) {
     RequestNotifyLayerTreeReady();
     mNeedLayerTreeReadyNotification = false;
@@ -2735,7 +2731,7 @@ TabParent::ApzAwareEventRoutingToChild(ScrollableLayerGuid* aOutTargetGuid,
                                        uint64_t* aOutInputBlockId,
                                        nsEventStatus* aOutApzResponse)
 {
-  if (AsyncPanZoomEnabled()) {
+  if (gfxPrefs::AsyncPanZoomEnabled()) {
     if (aOutTargetGuid) {
       *aOutTargetGuid = InputAPZContext::GetTargetLayerGuid();
 
@@ -2915,7 +2911,7 @@ TabParent::InjectTouchEvent(const nsAString& aType,
 NS_IMETHODIMP
 TabParent::GetUseAsyncPanZoom(bool* useAsyncPanZoom)
 {
-  *useAsyncPanZoom = AsyncPanZoomEnabled();
+  *useAsyncPanZoom = gfxPrefs::AsyncPanZoomEnabled();
   return NS_OK;
 }
 
@@ -3322,13 +3318,6 @@ TabParent::TakeDragVisualization(RefPtr<mozilla::gfx::SourceSurface>& aSurface,
   aDragAreaY = mDragAreaY;
 }
 
-bool
-TabParent::AsyncPanZoomEnabled() const
-{
-  nsCOMPtr<nsIWidget> widget = GetWidget();
-  return widget && widget->AsyncPanZoomEnabled();
-}
-
 NS_IMETHODIMP
 FakeChannel::OnAuthAvailable(nsISupports *aContext, nsIAuthInformation *aAuthInfo)
 {

dom/ipc/TabParent.h

@@ -448,8 +448,7 @@ protected:
 
     virtual bool RecvGetRenderFrameInfo(PRenderFrameParent* aRenderFrame,
                                         TextureFactoryIdentifier* aTextureFactoryIdentifier,
-                                        uint64_t* aLayersId,
+                                        uint64_t* aLayersId) override;
-                                        bool* aAsyncPanZoomEnabled) override;
 
     virtual bool RecvSetDimensions(const uint32_t& aFlags,
                                    const int32_t& aX, const int32_t& aY,
@@ -501,8 +500,6 @@ private:
 
     CSSPoint AdjustTapToChildWidget(const CSSPoint& aPoint);
 
-    bool AsyncPanZoomEnabled() const;
-
     // Update state prior to routing an APZ-aware event to the child process.
     // |aOutTargetGuid| will contain the identifier
     // of the APZC instance that handled the event. aOutTargetGuid may be null.

gfx/layers/Layers.h

@@ -669,10 +669,6 @@ public:
     return mAnimationReadyTime;
   }
 
-  virtual bool AsyncPanZoomEnabled() const {
-    return false;
-  }
-
 protected:
   nsRefPtr<Layer> mRoot;
   gfx::UserData mUserData;

gfx/layers/client/ClientLayerManager.cpp

@@ -213,7 +213,7 @@ ClientLayerManager::BeginTransactionWithTarget(gfxContext* aTarget)
   // platforms.
 #if defined(MOZ_WIDGET_ANDROID) || defined(MOZ_WIDGET_GONK)
   if (mWidget && mWidget->GetOwningTabChild()) {
-    mCompositorMightResample = AsyncPanZoomEnabled();
+    mCompositorMightResample = gfxPrefs::AsyncPanZoomEnabled();
   }
 #endif
 
@@ -782,12 +782,6 @@ ClientLayerManager::ProgressiveUpdateCallback(bool aHasPendingNewThebesContent,
 #endif
 }
 
-bool
-ClientLayerManager::AsyncPanZoomEnabled() const
-{
-  return mWidget && mWidget->AsyncPanZoomEnabled();
-}
-
 ClientLayer::~ClientLayer()
 {
   if (HasShadow()) {

gfx/layers/client/ClientLayerManager.h

@@ -250,9 +250,6 @@ public:
   void SetTransactionIdAllocator(TransactionIdAllocator* aAllocator) { mTransactionIdAllocator = aAllocator; }
 
   float RequestProperty(const nsAString& aProperty) override;
-
-  bool AsyncPanZoomEnabled() const override;
-
 protected:
   enum TransactionPhase {
     PHASE_NONE, PHASE_CONSTRUCTION, PHASE_DRAWING, PHASE_FORWARD

gfx/layers/client/ClientTiledPaintedLayer.cpp

@@ -257,7 +257,7 @@ ClientTiledPaintedLayer::UseProgressiveDraw() {
     return false;
   }
 
-  if (ClientManager()->AsyncPanZoomEnabled()) {
+  if (gfxPrefs::AsyncPanZoomEnabled()) {
     LayerMetricsWrapper scrollAncestor;
     GetAncestorLayers(&scrollAncestor, nullptr, nullptr);
     MOZ_ASSERT(scrollAncestor); // because mPaintData.mCriticalDisplayPort is non-empty

gfx/layers/composite/LayerManagerComposite.cpp

@@ -1329,12 +1329,6 @@ LayerComposite::SetLayerManager(LayerManagerComposite* aManager)
   mCompositor = aManager->GetCompositor();
 }
 
-bool
-LayerManagerComposite::AsyncPanZoomEnabled() const
-{
-  return mCompositor->GetWidget()->AsyncPanZoomEnabled();
-}
-
 nsIntRegion
 LayerComposite::GetFullyRenderedRegion() {
   if (TiledLayerComposer* tiled = GetTiledLayerComposer()) {

gfx/layers/composite/LayerManagerComposite.h

@@ -249,8 +249,6 @@ public:
 
   bool LastFrameMissedHWC() { return mLastFrameMissedHWC; }
 
-  bool AsyncPanZoomEnabled() const override;
-
 private:
   /** Region we're clipping our current drawing to. */
   nsIntRegion mClippingRegion;

gfx/layers/ipc/CompositorParent.cpp

@@ -662,9 +662,7 @@ CompositorParent::CompositorParent(nsIWidget* aWidget,
     sIndirectLayerTrees[mRootLayerTreeID].mParent = this;
   }
 
-  // The Compositor uses the APZ pref directly since it needs to know whether
+  if (gfxPrefs::AsyncPanZoomEnabled() &&
-  // to attempt to create the APZ machinery at all.
-  if (gfxPrefs::AsyncPanZoomEnabledDoNotUseDirectly() &&
 #if !defined(MOZ_B2G) && !defined(MOZ_WIDGET_ANDROID)
       // For XUL applications (everything but B2G on mobile and desktop, and
       // Firefox on Android) we only want to use APZ when E10S is enabled. If

gfx/thebes/gfxPlatform.cpp

@@ -2444,9 +2444,7 @@ DetectBadApzWheelInputPrefs()
 void
 gfxPlatform::GetApzSupportInfo(mozilla::widget::InfoObject& aObj)
 {
-  // This is only a diagnostic so we use the low-level pref to see whether
+  if (!gfxPrefs::AsyncPanZoomEnabled()) {
-  // C++ APZ is enabled at all.
-  if (!gfxPrefs::AsyncPanZoomEnabledDoNotUseDirectly()) {
     return;
   }
 

gfx/thebes/gfxPrefs.h

@@ -269,7 +269,7 @@ private:
   DECL_GFX_PREF(Live, "layers.acceleration.draw-fps.print-histogram",  FPSPrintHistogram, bool, false);
   DECL_GFX_PREF(Live, "layers.acceleration.draw-fps.write-to-file", WriteFPSToFile, bool, false);
   DECL_GFX_PREF(Once, "layers.acceleration.force-enabled",     LayersAccelerationForceEnabled, bool, false);
-  DECL_GFX_PREF(Once, "layers.async-pan-zoom.enabled",         AsyncPanZoomEnabledDoNotUseDirectly, bool, true);
+  DECL_GFX_PREF(Once, "layers.async-pan-zoom.enabled",         AsyncPanZoomEnabled, bool, false);
   DECL_GFX_PREF(Once, "layers.async-pan-zoom.separate-event-thread", AsyncPanZoomSeparateEventThread, bool, false);
   DECL_GFX_PREF(Once, "layers.async-video.enabled",            AsyncVideoEnabled, bool, true);
   DECL_GFX_PREF(Once, "layers.async-video-oop.enabled",        AsyncVideoOOPEnabled, bool, true);

image/ImageFactory.cpp

@@ -47,16 +47,11 @@ ComputeImageFlags(ImageURL* uri, const nsCString& aMimeType, bool isMultiPart)
 
   // We default to the static globals.
   bool isDiscardable = gfxPrefs::ImageMemDiscardable();
+  bool doDecodeOnlyOnDraw = gfxPrefs::ImageDecodeOnlyOnDrawEnabled() &&
+                            gfxPrefs::AsyncPanZoomEnabled();
   bool doDecodeImmediately = gfxPrefs::ImageDecodeImmediatelyEnabled();
   bool doDownscaleDuringDecode = gfxPrefs::ImageDownscaleDuringDecodeEnabled();
 
-  // We use the compositor APZ pref here since we don't have a widget to test.
-  // It's safe since this is an optimization, and the only platform
-  // ImageDecodeOnlyOnDraw is disabled on is B2G (where APZ is enabled in all
-  // widgets anyway).
-  bool doDecodeOnlyOnDraw = gfxPrefs::ImageDecodeOnlyOnDrawEnabled() &&
-                            gfxPrefs::AsyncPanZoomEnabledDoNotUseDirectly();
-
   // We want UI to be as snappy as possible and not to flicker. Disable
   // discarding and decode-only-on-draw for chrome URLS.
   bool isChrome = false;

layout/base/AccessibleCaretEventHub.cpp

@@ -8,7 +8,6 @@
 
 #include "AccessibleCaretLogger.h"
 #include "AccessibleCaretManager.h"
-#include "Layers.h"
 #include "gfxPrefs.h"
 #include "mozilla/MouseEvents.h"
 #include "mozilla/TextEvents.h"
@@ -412,9 +411,7 @@ AccessibleCaretEventHub::Init(nsIPresShell* aPresShell)
   }
 
 #if defined(MOZ_WIDGET_GONK)
-  if (layers::LayerManager* lm = mPresShell->GetLayerManager()) {
+  mUseAsyncPanZoom = gfxPrefs::AsyncPanZoomEnabled();
-    mUseAsyncPanZoom = lm->AsyncPanZoomEnabled();
-  }
 #endif
 
   docShell->AddWeakReflowObserver(this);

layout/base/FrameLayerBuilder.cpp

@@ -4751,7 +4751,7 @@ FrameLayerBuilder::BuildContainerLayerFor(nsDisplayListBuilder* aBuilder,
   if ((aContainerFrame->GetStateBits() & NS_FRAME_NO_COMPONENT_ALPHA) &&
       mRetainingManager &&
       mRetainingManager->ShouldAvoidComponentAlphaLayers() &&
-      !nsLayoutUtils::AsyncPanZoomEnabled(aContainerFrame))
+      !gfxPrefs::AsyncPanZoomEnabled())
   {
     flattenToSingleLayer = true;
   }
@@ -4783,7 +4783,7 @@ FrameLayerBuilder::BuildContainerLayerFor(nsDisplayListBuilder* aBuilder,
         mRetainingManager->ShouldAvoidComponentAlphaLayers() &&
         containerLayer->HasMultipleChildren() &&
         !flattenToSingleLayer &&
-        !nsLayoutUtils::AsyncPanZoomEnabled(aContainerFrame))
+        !gfxPrefs::AsyncPanZoomEnabled())
     {
       // Since we don't want any component alpha layers on BasicLayers, we repeat
       // the layer building process with this explicitely forced off.

layout/base/SelectionCarets.cpp

@@ -33,7 +33,6 @@
 #include "mozilla/dom/TreeWalker.h"
 #include "mozilla/Preferences.h"
 #include "mozilla/TouchEvents.h"
-#include "Layers.h"
 #include "TouchCaret.h"
 #include "nsFrameSelection.h"
 
@@ -117,9 +116,7 @@ SelectionCarets::Init()
   }
 
 #if defined(MOZ_WIDGET_GONK)
-  if (layers::LayerManager* lm = mPresShell->GetLayerManager()) {
+  mUseAsyncPanZoom = gfxPrefs::AsyncPanZoomEnabled();
-    mUseAsyncPanZoom = lm->AsyncPanZoomEnabled();
-  }
 #endif
 
   docShell->AddWeakReflowObserver(this);

layout/base/nsDisplayList.cpp

@@ -634,8 +634,7 @@ nsDisplayListBuilder::nsDisplayListBuilder(nsIFrame* aReferenceFrame,
       mHaveScrollableDisplayPort(false),
       mWindowDraggingAllowed(false),
       mIsBuildingForPopup(nsLayoutUtils::IsPopup(aReferenceFrame)),
-      mForceLayerForScrollParent(false),
+      mForceLayerForScrollParent(false)
-      mAsyncPanZoomEnabled(nsLayoutUtils::AsyncPanZoomEnabled(aReferenceFrame))
 {
   MOZ_COUNT_CTOR(nsDisplayListBuilder);
   PL_InitArenaPool(&mPool, "displayListArena", 1024,
@@ -2285,7 +2284,7 @@ nsDisplayBackgroundImage::ShouldFixToViewport(LayerManager* aManager)
 {
   // APZ doesn't (yet) know how to scroll the visible region for these type of
   // items, so don't layerize them if it's enabled.
-  if (nsLayoutUtils::UsesAsyncScrolling(mFrame) ||
+  if (nsLayoutUtils::UsesAsyncScrolling() ||
       (aManager && aManager->ShouldAvoidComponentAlphaLayers())) {
     return false;
   }
@@ -4210,7 +4209,7 @@ nsDisplaySubDocument::ComputeVisibility(nsDisplayListBuilder* aBuilder,
   // If APZ is enabled then don't allow this computation to influence
   // aVisibleRegion, on the assumption that the layer can be asynchronously
   // scrolled so we'll definitely need all the content under it.
-  if (!nsLayoutUtils::UsesAsyncScrolling(mFrame)) {
+  if (!nsLayoutUtils::UsesAsyncScrolling()) {
     bool snap;
     nsRect bounds = GetBounds(aBuilder, &snap);
     nsRegion removed;

layout/base/nsDisplayList.h

@@ -350,8 +350,8 @@ public:
     if (mMode == PAINTING) {
       // Note: this is the only place that gets to query LayoutEventRegionsEnabled
       // 'directly' - other code should call this function.
-      return gfxPrefs::LayoutEventRegionsEnabledDoNotUseDirectly() ||
+      return (gfxPrefs::LayoutEventRegionsEnabledDoNotUseDirectly() ||
-             mAsyncPanZoomEnabled;
+              gfxPrefs::AsyncPanZoomEnabled());
     }
     return false;
   }
@@ -976,7 +976,6 @@ private:
   bool                           mWindowDraggingAllowed;
   bool                           mIsBuildingForPopup;
   bool                           mForceLayerForScrollParent;
-  bool                           mAsyncPanZoomEnabled;
 };
 
 class nsDisplayItem;

layout/base/nsLayoutUtils.cpp

@@ -814,34 +814,6 @@ ApplyRectMultiplier(nsRect aRect, float aMultiplier)
   return nsRect(ceil(newX), ceil(newY), floor(newWidth), floor(newHeight));
 }
 
-bool
-nsLayoutUtils::UsesAsyncScrolling(nsIFrame* aFrame)
-{
-#ifdef MOZ_WIDGET_ANDROID
-  // We always have async scrolling for android
-  return true;
-#endif
-
-  return AsyncPanZoomEnabled(aFrame);
-}
-
-bool
-nsLayoutUtils::AsyncPanZoomEnabled(nsIFrame* aFrame)
-{
-  // We use this as a shortcut, since if the compositor will never use APZ,
-  // no widget will either.
-  if (!gfxPrefs::AsyncPanZoomEnabledDoNotUseDirectly()) {
-    return false;
-  }
-
-  nsIFrame *frame = nsLayoutUtils::GetDisplayRootFrame(aFrame);
-  nsIWidget* widget = frame->GetNearestWidget();
-  if (!widget) {
-    return false;
-  }
-  return widget->AsyncPanZoomEnabled();
-}
-
 // Return the maximum displayport size, based on the LayerManager's maximum
 // supported texture size. The result is in app units.
 static nscoord
@@ -1113,12 +1085,9 @@ nsLayoutUtils::SetDisplayPortMargins(nsIContent* aContent,
                             aMargins, aPriority),
                         nsINode::DeleteProperty<DisplayPortMarginsPropertyData>);
 
-  if (gfxPrefs::LayoutUseContainersForRootFrames()) {
+  if (nsLayoutUtils::UsesAsyncScrolling() && gfxPrefs::LayoutUseContainersForRootFrames()) {
     nsIFrame* rootScrollFrame = aPresShell->GetRootScrollFrame();
-    if (rootScrollFrame &&
+    if (rootScrollFrame && aContent == rootScrollFrame->GetContent()) {
-        aContent == rootScrollFrame->GetContent() &&
-        nsLayoutUtils::UsesAsyncScrolling(rootScrollFrame))
-    {
       // We are setting a root displayport for a document.
       // If we have APZ, then set a special flag on the pres shell so
       // that we don't get scrollbars drawn.
@@ -3006,7 +2975,7 @@ nsLayoutUtils::GetOrMaybeCreateDisplayPort(nsDisplayListBuilder& aBuilder,
   // Note: we only do this in processes where we do subframe scrolling to
   //       begin with (i.e., not in the parent process on B2G).
   if (aBuilder.IsPaintingToWindow() &&
-      nsLayoutUtils::AsyncPanZoomEnabled(aScrollFrame) &&
+      gfxPrefs::AsyncPanZoomEnabled() &&
       !aBuilder.HaveScrollableDisplayPort() &&
       scrollableFrame->WantAsyncScroll()) {
 
@@ -7853,6 +7822,17 @@ nsLayoutUtils::CalculateExpandedScrollableRect(nsIFrame* aFrame)
   return scrollableRect;
 }
 
+/* static */ bool
+nsLayoutUtils::UsesAsyncScrolling()
+{
+#ifdef MOZ_WIDGET_ANDROID
+  // We always have async scrolling for android
+  return true;
+#endif
+
+  return gfxPrefs::AsyncPanZoomEnabled();
+}
+
 /* static */ void
 nsLayoutUtils::DoLogTestDataForPaint(LayerManager* aManager,
                                      ViewID aScrollId,

layout/base/nsLayoutUtils.h

@@ -2514,16 +2514,10 @@ public:
   CalculateExpandedScrollableRect(nsIFrame* aFrame);
 
   /**
-   * Returns true if the widget owning the given frame uses asynchronous
+   * Returns true if we're using asynchronous scrolling (either through
-   * scrolling.
+   * APZ or the android frontend).
    */
-  static bool UsesAsyncScrolling(nsIFrame* aFrame);
+  static bool UsesAsyncScrolling();
-
-  /**
-   * Returns true if the widget owning the given frame has builtin APZ support
-   * enabled.
-   */
-  static bool AsyncPanZoomEnabled(nsIFrame* aFrame);
 
   /**
    * Log a key/value pair for APZ testing during a paint.

layout/base/nsPresShell.cpp

@@ -11041,10 +11041,10 @@ nsIPresShell::RecomputeFontSizeInflationEnabled()
 
   // Force-enabling font inflation always trumps the heuristics here.
   if (!FontSizeInflationForceEnabled()) {
-    if (TabChild* tab = TabChild::GetFrom(this)) {
+    if (TabChild::GetFrom(this)) {
       // We're in a child process.  Cancel inflation if we're not
       // async-pan zoomed.
-      if (!tab->AsyncPanZoomEnabled()) {
+      if (!gfxPrefs::AsyncPanZoomEnabled()) {
         mFontSizeInflationEnabled = false;
         return;
       }

layout/generic/nsGfxScrollFrame.cpp

@@ -1824,7 +1824,7 @@ ScrollFrameHelper::ScrollFrameHelper(nsContainerFrame* aOuter,
 
   if (IsAlwaysActive() &&
       gfxPrefs::LayersTilesEnabled() &&
-      !nsLayoutUtils::UsesAsyncScrolling(mOuter) &&
+      !nsLayoutUtils::UsesAsyncScrolling() &&
       mOuter->GetContent()) {
     // If we have tiling but no APZ, then set a 0-margin display port on
     // active scroll containers so that we paint by whole tile increments
@@ -2028,7 +2028,7 @@ ScrollFrameHelper::ScrollToWithOrigin(nsPoint aScrollPosition,
           mAsyncScroll = nullptr;
         }
 
-        if (nsLayoutUtils::AsyncPanZoomEnabled(mOuter)) {
+        if (gfxPrefs::AsyncPanZoomEnabled()) {
           // The animation will be handled in the compositor, pass the
           // information needed to start the animation and skip the main-thread
           // animation for this scroll.
@@ -2909,7 +2909,7 @@ ScrollFrameHelper::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
     shouldBuildLayer = true;
   } else {
     shouldBuildLayer =
-      nsLayoutUtils::AsyncPanZoomEnabled(mOuter) &&
+      gfxPrefs::AsyncPanZoomEnabled() &&
       WantAsyncScroll() &&
       // If we are using containers for root frames, and we are the root
       // scroll frame for the display root, then we don't need a scroll
@@ -3051,7 +3051,7 @@ ScrollFrameHelper::ComputeFrameMetrics(Layer* aLayer,
   // above the first one on a given layer. They will be applied by the
   // compositor instead, with async transforms for the scrollframes interspersed
   // between them.
-  bool omitClip = nsLayoutUtils::AsyncPanZoomEnabled(mOuter) && aOutput->Length() > 0;
+  bool omitClip = gfxPrefs::AsyncPanZoomEnabled() && aOutput->Length() > 0;
   if (!omitClip && (!gfxPrefs::LayoutUseContainersForRootFrames() || mAddClipRectToLayer)) {
     nsRect clip = nsRect(mScrollPort.TopLeft() + toReferenceFrame,
                          nsLayoutUtils::CalculateCompositionSizeForFrame(mOuter));
@@ -3355,8 +3355,7 @@ ScrollFrameHelper::ScrollBy(nsIntPoint aDelta,
   }
 
   if (aUnit == nsIScrollableFrame::DEVICE_PIXELS &&
-      !nsLayoutUtils::AsyncPanZoomEnabled(mOuter))
+      !gfxPrefs::AsyncPanZoomEnabled()) {
-  {
     // When APZ is disabled, we must track the velocity
     // on the main thread; otherwise, the APZC will manage this.
     mVelocityQueue.Sample(GetScrollPosition());

layout/ipc/RenderFrameParent.cpp

@@ -299,7 +299,6 @@ RenderFrameParent::RenderFrameParent(nsFrameLoader* aFrameLoader,
   , mFrameLoader(aFrameLoader)
   , mFrameLoaderDestroyed(false)
   , mBackgroundColor(gfxRGBA(1, 1, 1))
-  , mAsyncPanZoomEnabled(false)
 {
   *aSuccess = false;
   if (!mFrameLoader) {
@@ -309,9 +308,6 @@ RenderFrameParent::RenderFrameParent(nsFrameLoader* aFrameLoader,
   *aId = 0;
 
   nsRefPtr<LayerManager> lm = GetFrom(mFrameLoader);
-
-  mAsyncPanZoomEnabled = lm && lm->AsyncPanZoomEnabled();
-
   // Perhaps the document containing this frame currently has no presentation?
   if (lm && lm->GetBackendType() == LayersBackend::LAYERS_CLIENT) {
     *aTextureFactoryIdentifier =
@@ -329,7 +325,7 @@ RenderFrameParent::RenderFrameParent(nsFrameLoader* aFrameLoader,
         static_cast<ClientLayerManager*>(lm.get());
       clientManager->GetRemoteRenderer()->SendNotifyChildCreated(mLayersId);
     }
-    if (mAsyncPanZoomEnabled) {
+    if (gfxPrefs::AsyncPanZoomEnabled()) {
       mContentController = new RemoteContentController(this);
       CompositorParent::SetControllerForLayerTree(mLayersId, mContentController);
     }
@@ -350,7 +346,7 @@ RenderFrameParent::GetApzcTreeManager()
   // created and the static getter knows which CompositorParent is
   // instantiated with this layers ID. That's why try to fetch it when
   // we first need it and cache the result.
-  if (!mApzcTreeManager && mAsyncPanZoomEnabled) {
+  if (!mApzcTreeManager && gfxPrefs::AsyncPanZoomEnabled()) {
     mApzcTreeManager = CompositorParent::GetAPZCTreeManager(mLayersId);
   }
   return mApzcTreeManager.get();

layout/ipc/RenderFrameParent.h

@@ -151,8 +151,6 @@ private:
   gfxRGBA mBackgroundColor;
 
   nsRegion mTouchRegion;
-
-  bool mAsyncPanZoomEnabled;
 };
 
 } // namespace layout

layout/tools/reftest/reftest.js

@@ -744,7 +744,7 @@ function BuildConditionSandbox(aURL) {
     sandbox.Mulet = gB2GisMulet;
 
     try {
-        sandbox.asyncPanZoom = gContainingWindow.document.docShell.asyncPanZoomEnabled;
+        sandbox.asyncPanZoom = prefs.getBoolPref("layers.async-pan-zoom.enabled");
     } catch (e) {
         sandbox.asyncPanZoom = false;
     }

widget/PuppetWidget.cpp

@@ -354,7 +354,7 @@ PuppetWidget::DispatchInputEvent(WidgetInputEvent* aEvent)
 nsEventStatus
 PuppetWidget::DispatchAPZAwareEvent(WidgetInputEvent* aEvent)
 {
-  if (!AsyncPanZoomEnabled()) {
+  if (!gfxPrefs::AsyncPanZoomEnabled()) {
     nsEventStatus status = nsEventStatus_eIgnore;
     DispatchEvent(aEvent, status);
     return status;
@@ -493,12 +493,6 @@ PuppetWidget::SetConfirmedTargetAPZC(uint64_t aInputBlockId,
   }
 }
 
-bool
-PuppetWidget::AsyncPanZoomEnabled() const
-{
-  return mTabChild && mTabChild->AsyncPanZoomEnabled();
-}
-
 NS_IMETHODIMP_(bool)
 PuppetWidget::ExecuteNativeKeyBinding(NativeKeyBindingsType aType,
                                       const mozilla::WidgetKeyboardEvent& aEvent,

widget/PuppetWidget.h

@@ -135,7 +135,6 @@ public:
   nsEventStatus DispatchInputEvent(WidgetInputEvent* aEvent) override;
   void SetConfirmedTargetAPZC(uint64_t aInputBlockId,
                               const nsTArray<ScrollableLayerGuid>& aTargets) const override;
-  bool AsyncPanZoomEnabled() const override;
 
   NS_IMETHOD CaptureRollupEvents(nsIRollupListener* aListener,
                                  bool aDoCapture) override

widget/nsBaseWidget.cpp

@@ -1007,12 +1007,6 @@ nsBaseWidget::SetConfirmedTargetAPZC(uint64_t aInputBlockId,
     mAPZC.get(), setTargetApzcFunc, aInputBlockId, mozilla::Move(aTargets)));
 }
 
-bool
-nsBaseWidget::AsyncPanZoomEnabled() const
-{
-  return !!mAPZC;
-}
-
 nsEventStatus
 nsBaseWidget::ProcessUntransformedAPZEvent(WidgetInputEvent* aEvent,
                                            const ScrollableLayerGuid& aGuid,

widget/nsBaseWidget.h

@@ -242,8 +242,6 @@ public:
   void SetConfirmedTargetAPZC(uint64_t aInputBlockId,
                               const nsTArray<ScrollableLayerGuid>& aTargets) const override;
 
-  bool AsyncPanZoomEnabled() const override;
-
   void NotifyWindowDestroyed();
   void NotifySizeMoveDone();
   void NotifyWindowMoved(int32_t aX, int32_t aY);

widget/nsIWidget.h

@@ -1807,11 +1807,6 @@ class nsIWidget : public nsISupports {
     virtual void SetConfirmedTargetAPZC(uint64_t aInputBlockId,
                                         const nsTArray<mozilla::layers::ScrollableLayerGuid>& aTargets) const = 0;
 
-    /**
-     * Returns true if APZ is in use, false otherwise.
-     */
-    virtual bool AsyncPanZoomEnabled() const = 0;
-
     /**
      * Enables the dropping of files to a widget (XXX this is temporary)
      *