Bug 1205087 - Remove LayerManager parameter for ShouldFixToViewport. r=roc

layout/base/FrameLayerBuilder.cpp

@@ -1029,10 +1029,10 @@ public:
     MOZ_ASSERT_IF(isAtRoot, mContainerReferenceFrame == mBuilder->RootReferenceFrame());
     mContainerAnimatedGeometryRoot = isAtRoot
       ? mContainerReferenceFrame
-      : nsLayoutUtils::GetAnimatedGeometryRootFor(aContainerItem, aBuilder, aManager);
+      : nsLayoutUtils::GetAnimatedGeometryRootFor(aContainerItem, aBuilder);
     MOZ_ASSERT(nsLayoutUtils::IsAncestorFrameCrossDoc(mBuilder->RootReferenceFrame(),
                                                       mContainerAnimatedGeometryRoot));
-    NS_ASSERTION(!aContainerItem || !aContainerItem->ShouldFixToViewport(aManager),
+    NS_ASSERTION(!aContainerItem || !aContainerItem->ShouldFixToViewport(mBuilder),
                  "Container items never return true for ShouldFixToViewport");
     mContainerFixedPosFrame =
         FindFixedPosFrameForLayerData(mContainerAnimatedGeometryRoot, false);
@@ -3637,7 +3637,7 @@ ContainerState::ChooseAnimatedGeometryRoot(const nsDisplayList& aList,
     // Try using the actual active scrolled root of the backmost item, as that
     // should result in the least invalidation when scrolling.
     *aAnimatedGeometryRoot =
-      nsLayoutUtils::GetAnimatedGeometryRootFor(item, mBuilder, mManager);
+      nsLayoutUtils::GetAnimatedGeometryRootFor(item, mBuilder);
     return true;
   }
   return false;
@@ -3814,7 +3814,7 @@ ContainerState::ProcessDisplayItems(nsDisplayList* aList)
     const nsIFrame* animatedGeometryRoot;
     const nsIFrame* animatedGeometryRootForScrollMetadata = nullptr;
     const nsIFrame* realAnimatedGeometryRootOfItem =
-      nsLayoutUtils::GetAnimatedGeometryRootFor(item, mBuilder, mManager);
+      nsLayoutUtils::GetAnimatedGeometryRootFor(item, mBuilder);
     if (mFlattenToSingleLayer) {
       forceInactive = true;
       animatedGeometryRoot = lastAnimatedGeometryRoot;
@@ -3856,7 +3856,7 @@ ContainerState::ProcessDisplayItems(nsDisplayList* aList)
     }
 
     bool shouldFixToViewport = !animatedGeometryRoot->GetParent() &&
-      item->ShouldFixToViewport(mManager);
+      item->ShouldFixToViewport(mBuilder);
 
     // For items that are fixed to the viewport, remove their clip at the
     // display item level because additional areas could be brought into

layout/base/nsDisplayList.cpp

@@ -1459,6 +1459,22 @@ TriggerPendingAnimations(nsIDocument* aDocument,
                                          const_cast<TimeStamp*>(&aReadyTime));
 }
 
+LayerManager*
+nsDisplayListBuilder::GetWidgetLayerManager(nsView** aView, bool* aAllowRetaining)
+{
+  nsView* view = RootReferenceFrame()->GetView();
+  if (aView) {
+    *aView = view;
+  }
+  NS_ASSERTION(RootReferenceFrame() == nsLayoutUtils::GetDisplayRootFrame(RootReferenceFrame()),
+               "Reference frame must be a display root for us to use the layer manager");
+  nsIWidget* window = RootReferenceFrame()->GetNearestWidget();
+  if (window) {
+    return window->GetLayerManager(aAllowRetaining);
+  }
+  return nullptr;
+}
+
 /**
  * We paint by executing a layer manager transaction, constructing a
  * single layer representing the display list, and then making it the
@@ -1476,17 +1492,10 @@ already_AddRefed<LayerManager> nsDisplayList::PaintRoot(nsDisplayListBuilder* aB
   bool doBeginTransaction = true;
   nsView *view = nullptr;
   if (aFlags & PAINT_USE_WIDGET_LAYERS) {
-    nsIFrame* rootReferenceFrame = aBuilder->RootReferenceFrame();
-    view = rootReferenceFrame->GetView();
-    NS_ASSERTION(rootReferenceFrame == nsLayoutUtils::GetDisplayRootFrame(rootReferenceFrame),
-                 "Reference frame must be a display root for us to use the layer manager");
-    nsIWidget* window = rootReferenceFrame->GetNearestWidget();
-    if (window) {
-      layerManager = window->GetLayerManager(&allowRetaining);
-      if (layerManager) {
-        doBeginTransaction = !(aFlags & PAINT_EXISTING_TRANSACTION);
-        widgetTransaction = true;
-      }
+    layerManager = aBuilder->GetWidgetLayerManager(&view, &allowRetaining);
+    if (layerManager) {
+      doBeginTransaction = !(aFlags & PAINT_EXISTING_TRANSACTION);
+      widgetTransaction = true;
     }
   }
   if (!layerManager) {
@@ -2362,11 +2371,12 @@ nsDisplayBackgroundImage::IsNonEmptyFixedImage() const
 }
 
 bool
-nsDisplayBackgroundImage::ShouldFixToViewport(LayerManager* aManager)
+nsDisplayBackgroundImage::ShouldFixToViewport(nsDisplayListBuilder* aBuilder)
 {
   // APZ needs background-attachment:fixed images layerized for correctness.
+  nsRefPtr<LayerManager> layerManager = aBuilder->GetWidgetLayerManager();
   if (!nsLayoutUtils::UsesAsyncScrolling(mFrame) &&
-      aManager && aManager->ShouldAvoidComponentAlphaLayers()) {
+      layerManager && layerManager->ShouldAvoidComponentAlphaLayers()) {
     return false;
   }
 
@@ -3703,7 +3713,7 @@ RequiredLayerStateForChildren(nsDisplayListBuilder* aBuilder,
   LayerState result = LAYER_INACTIVE;
   for (nsDisplayItem* i = aList.GetBottom(); i; i = i->GetAbove()) {
     if (result == LAYER_INACTIVE &&
-        nsLayoutUtils::GetAnimatedGeometryRootFor(i, aBuilder, aManager) !=
+        nsLayoutUtils::GetAnimatedGeometryRootFor(i, aBuilder) !=
           aExpectedAnimatedGeometryRootForChildren) {
       result = LAYER_ACTIVE;
     }
@@ -3962,7 +3972,7 @@ nsDisplayOpacity::GetLayerState(nsDisplayListBuilder* aBuilder,
     return LAYER_ACTIVE;
 
   return RequiredLayerStateForChildren(aBuilder, aManager, aParameters, mList,
-    nsLayoutUtils::GetAnimatedGeometryRootFor(this, aBuilder, aManager));
+    nsLayoutUtils::GetAnimatedGeometryRootFor(this, aBuilder));
 }
 
 bool

layout/base/nsDisplayList.h

@@ -154,6 +154,8 @@ public:
     mMode = PLUGIN_GEOMETRY;
   }
 
+  mozilla::layers::LayerManager* GetWidgetLayerManager(nsView** aView = nullptr, bool* aAllowRetaining = nullptr);
+
   /**
    * @return true if the display is being built in order to determine which
    * frame is under the mouse position.
@@ -1284,7 +1286,7 @@ public:
    * @return true if the contents of this item are rendered fixed relative
    * to the nearest viewport.
    */
-  virtual bool ShouldFixToViewport(LayerManager* aManager)
+  virtual bool ShouldFixToViewport(nsDisplayListBuilder* aBuilder)
   { return false; }
 
   virtual bool ClearsBackground()
@@ -2393,7 +2395,7 @@ public:
   static nsRegion GetInsideClipRegion(nsDisplayItem* aItem, nsPresContext* aPresContext, uint8_t aClip,
                                       const nsRect& aRect, bool* aSnap);
 
-  virtual bool ShouldFixToViewport(LayerManager* aManager) override;
+  virtual bool ShouldFixToViewport(nsDisplayListBuilder* aBuilder) override;
 
 protected:
   typedef class mozilla::layers::ImageContainer ImageContainer;

layout/base/nsLayoutDebugger.cpp

@@ -163,7 +163,7 @@ PrintDisplayItemTo(nsDisplayListBuilder* aBuilder, nsDisplayItem* aItem,
   bool snap;
   nsRect rect = aItem->GetBounds(aBuilder, &snap);
   nsRect layerRect = rect -
-    nsLayoutUtils::GetAnimatedGeometryRootFor(aItem, aBuilder, nullptr)->
+    nsLayoutUtils::GetAnimatedGeometryRootFor(aItem, aBuilder)->
       GetOffsetToCrossDoc(aItem->ReferenceFrame());
   nscolor color;
   nsRect vis = aItem->GetVisibleRect();
@@ -194,7 +194,7 @@ PrintDisplayItemTo(nsDisplayListBuilder* aBuilder, nsDisplayItem* aItem,
     aStream << nsPrintfCString(" (opaque %d,%d,%d,%d)", r->x, r->y, r->width, r->height);
   }
 
-  if (aItem->ShouldFixToViewport(nullptr)) {
+  if (aItem->ShouldFixToViewport(aBuilder)) {
     aStream << " fixed";
   }
 

layout/base/nsLayoutUtils.cpp

@@ -1843,11 +1843,10 @@ nsLayoutUtils::GetAnimatedGeometryRootForFrame(nsDisplayListBuilder* aBuilder,
 
 nsIFrame*
 nsLayoutUtils::GetAnimatedGeometryRootFor(nsDisplayItem* aItem,
-                                          nsDisplayListBuilder* aBuilder,
-                                          LayerManager* aManager)
+                                          nsDisplayListBuilder* aBuilder)
 {
   nsIFrame* f = aItem->Frame();
-  if (aItem->ShouldFixToViewport(aManager)) {
+  if (aItem->ShouldFixToViewport(aBuilder)) {
     // Make its active scrolled root be the active scrolled root of
     // the enclosing viewport, since it shouldn't be scrolled by scrolled
     // frames in its document. InvalidateFixedBackgroundFramesFromList in

layout/base/nsLayoutUtils.h

@@ -550,8 +550,7 @@ public:
    * geometry root.
    */
   static nsIFrame* GetAnimatedGeometryRootFor(nsDisplayItem* aItem,
-                                              nsDisplayListBuilder* aBuilder,
-                                              mozilla::layers::LayerManager* aManager);
+                                              nsDisplayListBuilder* aBuilder);
 
   /**
    * Finds the nearest ancestor frame to aFrame that is considered to have (or

layout/generic/nsCanvasFrame.h

@@ -279,7 +279,7 @@ public:
     mFrame->Properties().Delete(nsIFrame::CachedBackgroundImageDT());
   }
 
-  virtual bool ShouldFixToViewport(LayerManager* aManager) override
+  virtual bool ShouldFixToViewport(nsDisplayListBuilder* aBuilder) override
   {
     // Put background-attachment:fixed canvas background images in their own
     // compositing layer. Since we know their background painting area can't