Don't restart the ImageQualityController timer unless it is already half over.

third_party/WebKit/Source/core/layout/ImageQualityController.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 41 matching lines @@
 public:
     ~ImageQualityController();
 
     static ImageQualityController* imageQualityController();
 
     static void remove(LayoutObject&);
 
     InterpolationQuality chooseInterpolationQuality(const LayoutObject&, Image*, const void* layer, const LayoutSize&);
 
 private:
+    static const double cLowQualityTimeThreshold;
+    static const double cTimerRestartThreshold;
+
     ImageQualityController();
 
     static bool has(const LayoutObject&);
     void set(const LayoutObject&, LayerSizeMap* innerMap, const void* layer, const LayoutSize&, bool isResizing);
 
-    bool shouldPaintAtLowQuality(const LayoutObject&, Image*, const void* layer, const LayoutSize&);
+    bool shouldPaintAtLowQuality(const LayoutObject&, Image*, const void* layer, const LayoutSize&, double lastFrameTimeMonotonic);
     void removeLayer(const LayoutObject&, LayerSizeMap* innerMap, const void* layer);
     void objectDestroyed(const LayoutObject&);
     bool isEmpty() { return m_objectLayerSizeMap.isEmpty(); }
 
     void highQualityRepaintTimerFired(Timer<ImageQualityController>*);
-    void restartTimer();
+    void restartTimer(double lastFrameTimeMonotonic);
 
     // Only for use in testing.
     void setTimer(Timer<ImageQualityController>*);
 
     ObjectLayerSizeMap m_objectLayerSizeMap;
     OwnPtr<Timer<ImageQualityController>> m_timer;
+    double m_frameTimeWhenTimerStarted;
 
     // For calling set().
     FRIEND_TEST_ALL_PREFIXES(LayoutPartTest, DestroyUpdatesImageQualityController);
 
     // For calling setTimer(),
     FRIEND_TEST_ALL_PREFIXES(ImageQualityControllerTest, LowQualityFilterForResizingImage);
     FRIEND_TEST_ALL_PREFIXES(ImageQualityControllerTest, MediumQualityFilterForNotAnimatedWhileAnotherAnimates);
     FRIEND_TEST_ALL_PREFIXES(ImageQualityControllerTest, DontKickTheAnimationTimerWhenPaintingAtTheSameSize);
+    FRIEND_TEST_ALL_PREFIXES(ImageQualityControllerTest, DontRestartTimerUnlessAdvanced);
 };
 
 } // namespace blink
 
 #endif