Bug 940952 - Replace apzc GeckoContentController pan notifications with more general purpose transform notifications. r=botond

browser/metro/base/content/apzc.js

@@ -28,8 +28,7 @@ var APZCObserver = {
     }
 
     let os = Services.obs;
-    os.addObserver(this, "apzc-handle-pan-begin", false);
-    os.addObserver(this, "apzc-handle-pan-end", false);
+    os.addObserver(this, "apzc-transform-begin", false);
 
     // Fired by ContentAreaObserver
     window.addEventListener("SizeChanged", this, true);
@@ -45,8 +44,7 @@ var APZCObserver = {
     }
 
     let os = Services.obs;
-    os.removeObserver(this, "apzc-handle-pan-begin");
-    os.removeObserver(this, "apzc-handle-pan-end");
+    os.removeObserver(this, "apzc-transform-begin");
 
     window.removeEventListener("SizeChanged", this, true);
 
@@ -86,7 +84,7 @@ var APZCObserver = {
   },
 
   observe: function ao_observe(aSubject, aTopic, aData) {
-    if (aTopic == "apzc-handle-pan-begin") {
+    if (aTopic == "apzc-transform-begin") {
       // When we're panning, hide the main scrollbars by setting imprecise
       // input (which sets a property on the browser which hides the scrollbar
       // via CSS).  This reduces jittering from left to right. We may be able

browser/metro/base/content/helperui/SelectionHelperUI.js

@@ -358,13 +358,13 @@ var SelectionHelperUI = {
                                event.clientX, event.clientY);
         break;
 
-      case "apzc-handle-pan-begin":
+      case "apzc-transform-begin":
         if (this.isActive && this.layerMode == kContentLayer) {
           this._hideMonocles();
         }
         break;
 
-      case "apzc-handle-pan-end":
+      case "apzc-transform-end":
         // The selection range callback will check to see if the new
         // position is off the screen, in which case it shuts down and
         // clears the selection.
@@ -549,8 +549,8 @@ var SelectionHelperUI = {
   init: function () {
     let os = Services.obs;
     os.addObserver(this, "attach_edit_session_to_content", false);
-    os.addObserver(this, "apzc-handle-pan-begin", false);
-    os.addObserver(this, "apzc-handle-pan-end", false);
+    os.addObserver(this, "apzc-transform-begin", false);
+    os.addObserver(this, "apzc-transform-end", false);
   },
 
   _init: function _init(aMsgTarget) {

gfx/layers/ipc/AsyncPanZoomController.cpp

@@ -992,7 +992,7 @@ bool AsyncPanZoomController::DoFling(const TimeDuration& aDelta) {
   if (!shouldContinueFlingX && !shouldContinueFlingY) {
     SendAsyncScrollEvent();
     RequestContentRepaint();
-    mState = NOTHING;
+    SetState(NOTHING);
     return false;
   }
 
@@ -1016,8 +1016,7 @@ bool AsyncPanZoomController::DoFling(const TimeDuration& aDelta) {
 }
 
 void AsyncPanZoomController::CancelAnimation() {
-  ReentrantMonitorAutoEnter lock(mMonitor);
-  mState = NOTHING;
+  SetState(NOTHING);
 }
 
 void AsyncPanZoomController::SetCompositorParent(CompositorParent* aCompositorParent) {
@@ -1268,7 +1267,7 @@ bool AsyncPanZoomController::SampleContentTransformForFrame(const TimeStamp& aSa
       requestAnimationFrame = true;
 
       if (aSampleTime - mAnimationStartTime >= ZOOM_TO_DURATION) {
-        mState = NOTHING;
+        SetState(NOTHING);
         SendAsyncScrollEvent();
         RequestContentRepaint();
       }
@@ -1376,7 +1375,7 @@ void AsyncPanZoomController::NotifyLayersUpdated(const FrameMetrics& aLayerMetri
     mY.CancelTouch();
 
     mFrameMetrics = aLayerMetrics;
-    mState = NOTHING;
+    SetState(NOTHING);
   } else {
     // If we're not taking the aLayerMetrics wholesale we still need to pull
     // in some things into our local mFrameMetrics because these things are
@@ -1554,14 +1553,18 @@ void AsyncPanZoomController::SetState(PanZoomState aNewState) {
   }
 
   if (mGeckoContentController) {
-    if (IsPanningState(oldState) && !IsPanningState(aNewState)) {
-      mGeckoContentController->HandlePanEnd();
-    } else if (!IsPanningState(oldState) && IsPanningState(aNewState)) {
-      mGeckoContentController->HandlePanBegin();
+    if (!IsTransformingState(oldState) && IsTransformingState(aNewState)) {
+      mGeckoContentController->NotifyTransformBegin();
+    } else if (IsTransformingState(oldState) && !IsTransformingState(aNewState)) {
+      mGeckoContentController->NotifyTransformEnd();
     }
   }
 }
 
+bool AsyncPanZoomController::IsTransformingState(PanZoomState aState) {
+  return !(aState == NOTHING || aState == TOUCHING || aState == WAITING_LISTENERS);
+}
+
 bool AsyncPanZoomController::IsPanningState(PanZoomState aState) {
   return (aState == PANNING || aState == PANNING_LOCKED_X || aState == PANNING_LOCKED_Y);
 }

gfx/layers/ipc/AsyncPanZoomController.h

@@ -510,6 +510,19 @@ private:
                     prevented the default actions yet. we still need to abort animations. */
   };
 
+  /**
+   * Helper to set the current state. Holds the monitor before actually setting
+   * it and fires content controller events based on state changes. Always set
+   * the state using this call, do not set it directly.
+   */
+  void SetState(PanZoomState aState);
+
+  /**
+   * Internal helpers for checking general state of this apzc.
+   */
+  bool IsTransformingState(PanZoomState aState);
+  bool IsPanningState(PanZoomState mState);
+
   enum AxisLockMode {
     FREE,     /* No locking at all */
     STANDARD, /* Default axis locking mode that remains locked until pan ends*/
@@ -518,15 +531,6 @@ private:
 
   static AxisLockMode GetAxisLockMode();
 
-  /**
-   * Helper to set the current state. Holds the monitor before actually setting
-   * it. If the monitor is already held by the current thread, it is safe to
-   * instead use: |mState = NEWSTATE;|
-   */
-  void SetState(PanZoomState aState);
-
-  bool IsPanningState(PanZoomState mState);
-
   uint64_t mLayersId;
   nsRefPtr<CompositorParent> mCompositorParent;
   TaskThrottler mPaintThrottler;

gfx/layers/ipc/GeckoContentController.h

@@ -77,14 +77,12 @@ public:
   }
 
   /**
-   * Request any special actions be performed when panning starts
+   * General tranformation notices for consumers. These fire any time
+   * the apzc is modifying the view, including panning, zooming, and
+   * fling.
    */
-  virtual void HandlePanBegin() {}
-
-  /**
-   * Request any special actions be performed when panning ends
-   */
-  virtual void HandlePanEnd() {}
+  virtual void NotifyTransformBegin() {}
+  virtual void NotifyTransformEnd() {}
 
   GeckoContentController() {}
   virtual ~GeckoContentController() {}

widget/windows/winrt/APZController.cpp

@@ -317,18 +317,44 @@ APZController::PostDelayedTask(Task* aTask, int aDelayMs)
   MessageLoop::current()->PostDelayedTask(FROM_HERE, aTask, aDelayMs);
 }
 
-// async scroll notifications
+// apzc notifications
+
+class TransformedStartEvent : public nsRunnable
+{
+  NS_IMETHOD Run() {
+    MetroUtils::FireObserver("apzc-transform-start", L"");
+    return NS_OK;
+  }
+};
+
+class TransformedEndEvent : public nsRunnable
+{
+  NS_IMETHOD Run() {
+    MetroUtils::FireObserver("apzc-transform-end", L"");
+    return NS_OK;
+  }
+};
 
 void
-APZController::HandlePanBegin()
+APZController::NotifyTransformBegin()
 {
-  MetroUtils::FireObserver("apzc-handle-pan-begin", L"");
+  if (NS_IsMainThread()) {
+    MetroUtils::FireObserver("apzc-transform-begin", L"");
+    return;
+  }
+  nsCOMPtr<nsIRunnable> runnable = new TransformedStartEvent();
+  NS_DispatchToMainThread(runnable);
 }
 
 void
-APZController::HandlePanEnd()
+APZController::NotifyTransformEnd()
 {
-  MetroUtils::FireObserver("apzc-handle-pan-end", L"");
+  if (NS_IsMainThread()) {
+    MetroUtils::FireObserver("apzc-transform-end", L"");
+    return;
+  }
+  nsCOMPtr<nsIRunnable> runnable = new TransformedEndEvent();
+  NS_DispatchToMainThread(runnable);
 }
 
 } } }

widget/windows/winrt/APZController.h

@@ -37,8 +37,8 @@ public:
   virtual void HandleLongTap(const mozilla::CSSIntPoint& aPoint, int32_t aModifiers);
   virtual void SendAsyncScrollDOMEvent(bool aIsRoot, const mozilla::CSSRect &aContentRect, const mozilla::CSSSize &aScrollableSize);
   virtual void PostDelayedTask(Task* aTask, int aDelayMs);
-  virtual void HandlePanBegin();
-  virtual void HandlePanEnd();
+  virtual void NotifyTransformBegin();
+  virtual void NotifyTransformEnd();
   
   void SetWidgetListener(nsIWidgetListener* aWidgetListener);
   void UpdateScrollOffset(const mozilla::layers::ScrollableLayerGuid& aScrollLayerId, CSSIntPoint& aScrollOffset);