Don't recreate SkImages for high-res (GIF, WEBP...) animations.

third_party/WebKit/Source/platform/graphics/BitmapImageTest.cpp

 /*
  * 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 51 matching lines @@
     BitmapImageTest(bool enableDeferredDecoding) : m_enableDeferredDecoding(enableDeferredDecoding) { }
 
     static PassRefPtr<SharedBuffer> readFile(const char* fileName)
     {
         String filePath = testing::blinkRootDir();
         filePath.append(fileName);
         return testing::readFromFile(filePath);
     }
 
     // Accessors to BitmapImage's protected methods.
-    void destroyDecodedData(bool destroyAll) { m_image->destroyDecodedData(destroyAll); }
+    void destroyDecodedData() { m_image->destroyDecodedData(); }
     size_t frameCount() { return m_image->frameCount(); }
     void frameAtIndex(size_t index)
     {
         m_image->frameAtIndex(index);
     }
     void setCurrentFrame(size_t frame) { m_image->m_currentFrame = frame; }
     size_t frameDecodedSize(size_t frame) { return m_image->m_frames[frame].m_frameBytes; }
     size_t decodedFramesCount() const { return m_image->m_frames.size(); }
 
     void setFirstFrameNotComplete() { m_image->m_frames[0].m_isComplete = false; }
@@ skipping 55 matching lines @@
         m_image = BitmapImage::create(m_imageObserver.get());
     }
 
     OwnPtrWillBePersistent<FakeImageObserver> m_imageObserver;
     RefPtr<BitmapImage> m_image;
 
 private:
     bool m_enableDeferredDecoding;
 };
 
-TEST_F(BitmapImageTest, destroyDecodedDataExceptCurrentFrame)
-{
-    loadImage("/LayoutTests/fast/images/resources/animated-10color.gif");
-    size_t totalSize = decodedSize();
-    size_t frame = frameCount() / 2;
-    setCurrentFrame(frame);
-    size_t size = frameDecodedSize(frame);
-    destroyDecodedData(false);
-    EXPECT_LT(m_imageObserver->m_lastDecodedSizeChangedDelta, 0);
-    EXPECT_GE(m_imageObserver->m_lastDecodedSizeChangedDelta, -static_cast<int>(totalSize - size));
-}
-
 TEST_F(BitmapImageTest, destroyAllDecodedData)
 {
     loadImage("/LayoutTests/fast/images/resources/animated-10color.gif");
     size_t totalSize = decodedSize();
     EXPECT_GT(totalSize, 0u);
-    destroyDecodedData(true);
+    destroyDecodedData();
     EXPECT_EQ(-static_cast<int>(totalSize), m_imageObserver->m_lastDecodedSizeChangedDelta);
     EXPECT_EQ(0u, decodedSize());
 }
 
 TEST_F(BitmapImageTest, maybeAnimated)
 {
     loadImage("/LayoutTests/fast/images/resources/gif-loop-count.gif");
     for (size_t i = 0; i < frameCount(); ++i) {
         EXPECT_TRUE(m_image->maybeAnimated());
         advanceAnimation();
@@ skipping 83 matching lines @@
 
 TEST_F(BitmapImageTest, correctDecodedDataSize)
 {
     // When requesting a frame of a multi-frame GIF causes another frame to be
     // decoded as well, both frames' sizes should be reported by the source and
     // thus included in the decoded size changed notification.
     loadImage("/LayoutTests/fast/images/resources/anim_none.gif", false);
     frameAtIndex(1);
     int frameSize = static_cast<int>(m_image->size().area() * sizeof(ImageFrame::PixelData));
     EXPECT_EQ(frameSize * 2, m_imageObserver->m_lastDecodedSizeChangedDelta);
-
-    // Trying to destroy all data except an undecoded frame should cause the
-    // decoder to seek backwards and preserve the most recent previous frame
-    // necessary to decode that undecoded frame, and destroy all other frames.
-    setCurrentFrame(2);
-    destroyDecodedData(false);
-    EXPECT_EQ(-frameSize, m_imageObserver->m_lastDecodedSizeChangedDelta);
 }
 
 TEST_F(BitmapImageTest, recachingFrameAfterDataChanged)
 {
     loadImage("/LayoutTests/fast/images/resources/green.jpg");
     setFirstFrameNotComplete();
     EXPECT_GT(m_imageObserver->m_lastDecodedSizeChangedDelta, 0);
     m_imageObserver->m_lastDecodedSizeChangedDelta = 0;
 
     // Calling dataChanged causes the cache to flush, but doesn't affect the
@@ skipping 11 matching lines @@
 };
 
 TEST_F(BitmapImageDeferredDecodingTest, correctDecodedDataSize)
 {
     // When deferred decoding is enabled, requesting any one frame shouldn't
     // result in decoding any other frames.
     loadImage("/LayoutTests/fast/images/resources/anim_none.gif", false);
     frameAtIndex(1);
     int frameSize = static_cast<int>(m_image->size().area() * sizeof(ImageFrame::PixelData));
     EXPECT_EQ(frameSize, m_imageObserver->m_lastDecodedSizeChangedDelta);
     frameAtIndex(0);

[Peter Kasting, 2016/04/05 01:55:58]

This frameAtIndex() call should be removed as well.

-
-    // Trying to destroy all data except an undecoded frame should go ahead and
-    // destroy all other frames.
-    setCurrentFrame(2);
-    destroyDecodedData(false);
-    EXPECT_EQ(-frameSize * 2, m_imageObserver->m_lastDecodedSizeChangedDelta);
 }
 
 } // namespace blink