Checking if frame is complete and access duration doesn't need a decode

Source/core/platform/graphics/BitmapImage.cpp

 /*
  * Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2004, 2005, 2006, 2008 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 290 matching lines @@
 
 PassNativeImagePtr BitmapImage::frameAtIndex(size_t index)
 {
     if (!ensureFrameIsCached(index))
         return 0;
     return m_frames[index].m_frame;
 }
 
 bool BitmapImage::frameIsCompleteAtIndex(size_t index)
 {
-    if (!ensureFrameIsCached(index))
-        return false;
-    return m_frames[index].m_isComplete;
+    if (index < m_frames.size() && m_frames[index].m_haveMetadata && m_frames[index].m_isComplete)
+        return true;
+    return m_source.frameIsCompleteAtIndex(index);
 }
 
 float BitmapImage::frameDurationAtIndex(size_t index)
 {
-    if (!ensureFrameIsCached(index))
-        return 0;
-    return m_frames[index].m_duration;
+    if (index < m_frames.size() && m_frames[index].m_haveMetadata)
+        return m_frames[index].m_duration;
+    return m_source.frameDurationAtIndex(index);
 }
 
 PassNativeImagePtr BitmapImage::nativeImageForCurrentFrame()
 {
     return frameAtIndex(currentFrame());
 }
 
 bool BitmapImage::frameHasAlphaAtIndex(size_t index)
 {
     if (m_frames.size() <= index)
@@ skipping 250 matching lines @@
 }
 
 void FrameData::reportMemoryUsage(MemoryObjectInfo* memoryObjectInfo) const
 {
     MemoryClassInfo info(memoryObjectInfo, this, PlatformMemoryTypes::Image);
     memoryObjectInfo->setClassName("FrameData");
     info.addMember(m_frame, "frame", WTF::RetainingPointer);
 }
 
 }