Bug 1245285 - part 2, Prevent Zoom and Overscroll animations from repainting durring animation r=botond

gfx/layers/apz/src/AsyncPanZoomAnimation.h

@@ -49,11 +49,14 @@ public:
     return Move(mDeferredTasks);
   }
 
-public:
   virtual WheelScrollAnimation* AsWheelScrollAnimation() {
     return nullptr;
   }
 
+  virtual bool WantsRepaints() {
+    return true;
+  }
+
 protected:
   // Protected destructor, to discourage deletion outside of Release():
   virtual ~AsyncPanZoomAnimation()

gfx/layers/apz/src/AsyncPanZoomController.cpp

@@ -647,6 +647,11 @@ public:
     return true;
   }
 
+  virtual bool WantsRepaints() override
+  {
+    return false;
+  }
+
 private:
   TimeDuration mDuration;
   const TimeDuration mTotalDuration;
@@ -698,6 +703,12 @@ public:
     }
     return true;
   }
+
+  virtual bool WantsRepaints() override
+  {
+    return false;
+  }
+
 private:
   AsyncPanZoomController& mApzc;
 };
@@ -2940,12 +2951,15 @@ bool AsyncPanZoomController::UpdateAnimation(const TimeStamp& aSampleTime,
 
   if (mAnimation) {
     bool continueAnimation = mAnimation->Sample(mFrameMetrics, sampleTimeDelta);
+    bool wantsRepaints = mAnimation->WantsRepaints();
     *aOutDeferredTasks = mAnimation->TakeDeferredTasks();
     if (!continueAnimation) {
       mAnimation = nullptr;
       SetState(NOTHING);
     }
-    RequestContentRepaint();
+    if (wantsRepaints) {
+      RequestContentRepaint();
+    }
     UpdateSharedCompositorFrameMetrics();
     return true;
   }