Fix under-invalidation of media buffered ranges

third_party/WebKit/Source/core/html/shadow/MediaControls.h

Index: third_party/WebKit/Source/core/html/shadow/MediaControls.h
diff --git a/third_party/WebKit/Source/core/html/shadow/MediaControls.h b/third_party/WebKit/Source/core/html/shadow/MediaControls.h
index 8b5892229a9919dc173917c16384231f1a0d6e78..0487d323da8766917c804bc9cc13c31e8a382a3d 100644
--- a/third_party/WebKit/Source/core/html/shadow/MediaControls.h
+++ b/third_party/WebKit/Source/core/html/shadow/MediaControls.h
@@ -34,6 +34,7 @@ namespace blink {
 
 class Event;
 class TextTrackContainer;
+class TimeRanges;
 
 class CORE_EXPORT MediaControls final : public HTMLDivElement {
 public:
@@ -127,6 +128,11 @@ private:
     void defaultEventHandler(Event*) override;
     bool containsRelatedTarget(Event*);
 
+    void updateTimelinePosition();
+    void updateBufferedRanges();
+    void startOrStopBufferedRangesPaintInvalidationTimer();
+    void bufferedRangesPaintInvalidationTimerFired(TimerBase*);
+
     Member<HTMLMediaElement> m_mediaElement;
 
     // Media control elements.
@@ -155,6 +161,9 @@ private:
     int m_panelWidth;
 
     bool m_allowHiddenVolumeControls : 1;
+
+    Timer<MediaControls> m_bufferedRangesPaintInvalidationTimer;
+    Member<TimeRanges> m_lastBufferedRanges;
 };
 
 DEFINE_ELEMENT_TYPE_CASTS(MediaControls, isMediaControls());