Save a bitmap copy when advancing to dependent GIF and WebP animation frames

third_party/WebKit/Source/platform/image-decoders/ImageFrame.cpp

 /*
  * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.
  * Copyright (C) 2008, 2009 Google, Inc.
  *
  * 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 75 matching lines @@
 bool ImageFrame::copyBitmapData(const ImageFrame& other)
 {
     if (this == &other)
         return true;
 
     m_hasAlpha = other.m_hasAlpha;
     m_bitmap.reset();
     return other.m_bitmap.copyTo(&m_bitmap, other.m_bitmap.colorType());
 }
 
+void ImageFrame::takeBitmapData(ImageFrame* other)
+{
+    DCHECK(other);
+    if (this == other)
+        return;
+
+    m_hasAlpha = other->m_hasAlpha;
+    m_bitmap.reset();
+    m_bitmap.swap(other->m_bitmap);
+    other->m_status = FrameEmpty;
+}
+
 bool ImageFrame::setSize(int newWidth, int newHeight)
 {
     // setSize() should only be called once, it leaks memory otherwise.
     ASSERT(!width() && !height());
 
     m_bitmap.setInfo(SkImageInfo::MakeN32(newWidth, newHeight,
         m_premultiplyAlpha ? kPremul_SkAlphaType : kUnpremul_SkAlphaType));
     if (!m_bitmap.tryAllocPixels(m_allocator, 0))
         return false;
 
@@ skipping 39 matching lines @@
     // If the frame is not fully loaded, there will be transparent pixels,
     // so we can't tell skia we're opaque, even for image types that logically
     // always are (e.g. jpeg).
     if (!m_hasAlpha && m_status == FrameComplete)
         return kOpaque_SkAlphaType;
 
     return m_premultiplyAlpha ? kPremul_SkAlphaType : kUnpremul_SkAlphaType;
 }
 
 } // namespace blink