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

third_party/WebKit/Source/platform/exported/WebImage.cpp

 /*
  * Copyright (C) 2009 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 60 matching lines @@
         if (frameArea < (desiredSize.width * desiredSize.height))
             break; // No more frames that are large enough.
 
         if (!i || (frameArea < frameAreaAtIndex)) {
             index = i; // Closer to desired area than previous best match.
             frameAreaAtIndex = frameArea;
         }
     }
 
     ImageFrame* frame = decoder->frameBufferAtIndex(index);
-    if (!frame)
+    if (!frame || decoder->failed())
         return WebImage();
 
-    return WebImage(frame->bitmap());
+    DCHECK_EQ(frame->getStatus(), ImageFrame::FrameComplete);
+    SkBitmap bitmap = frame->bitmap();
+    bitmap.setImmutable();
+    return WebImage(bitmap);
 }
 
 WebVector<WebImage> WebImage::framesFromData(const WebData& data)
 {
     // This is to protect from malicious images. It should be big enough that it's never hit in pracice.
     const size_t maxFrameCount = 8;
 
     RefPtr<SharedBuffer> buffer = PassRefPtr<SharedBuffer>(data);
     std::unique_ptr<ImageDecoder> decoder(ImageDecoder::create(ImageDecoder::determineImageType(*buffer.get()), ImageDecoder::AlphaPremultiplied, ImageDecoder::GammaAndColorProfileIgnored));
     if (!decoder)
@@ skipping 12 matching lines @@
     for (size_t i = 0; i < std::min(frameCount, maxFrameCount); ++i) {
         const IntSize frameSize = decoder->frameSizeAtIndex(i);
         if (frameSize == lastSize)
             continue;
         lastSize = frameSize;
 
         ImageFrame* frame = decoder->frameBufferAtIndex(i);
         if (!frame)
             continue;
 
-        const SkBitmap& bitmap = frame->bitmap();
-        if (!bitmap.isNull() && bitmap.isImmutable())
+        SkBitmap bitmap = frame->bitmap();
+        if (!bitmap.isNull() && frame->getStatus() == ImageFrame::FrameComplete) {
+            bitmap.setImmutable();
             frames.append(WebImage(bitmap));
+        }
     }
 
     return frames;
 }
 
 void WebImage::reset()
 {
     m_bitmap.reset();
 }
 
@@ skipping 15 matching lines @@
 WebImage::WebImage(const PassRefPtr<Image>& image)
 {
     if (!image)
         return;
 
     if (RefPtr<SkImage> skImage = image->imageForCurrentFrame())
         skImage->asLegacyBitmap(&m_bitmap, SkImage::kRO_LegacyBitmapMode);
 }
 
 } // namespace blink