Deferred GIF image decodes should report decode failures

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

 /*
  * Copyright (C) 2012 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:
  * 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 66 matching lines @@
     return s_enabled;
 }
 
 String DeferredImageDecoder::filenameExtension() const
 {
     return m_actualDecoder ? m_actualDecoder->filenameExtension() : m_filenameExtension;
 }
 
 PassRefPtr<SkImage> DeferredImageDecoder::createFrameAtIndex(size_t index)
 {
+    if (m_frameGenerator && m_frameGenerator->decodeFailed())
+        return nullptr;
+
     prepareLazyDecodedFrames();
 
     if (index < m_frameData.size()) {
+        FrameData* frameData = &m_frameData[index];
         // ImageFrameGenerator has the latest known alpha state. There will be a
         // performance boost if this frame is opaque.
-        FrameData* frameData = &m_frameData[index];
+        ASSERT(m_frameGenerator);
         frameData->m_hasAlpha = m_frameGenerator->hasAlpha(index);
         frameData->m_frameBytes = m_size.area() * sizeof(ImageFrame::PixelData);
         return createFrameImageAtIndex(index, !frameData->m_hasAlpha);
     }
 
-    if (!m_actualDecoder)
+    if (!m_actualDecoder || m_actualDecoder->failed())
         return nullptr;
 
     ImageFrame* frame = m_actualDecoder->frameBufferAtIndex(index);
     if (!frame || frame->status() == ImageFrame::FrameEmpty)
         return nullptr;
 
     return adoptRef(SkImage::NewFromBitmap(frame->bitmap()));
 }
 
 void DeferredImageDecoder::setData(SharedBuffer& data, bool allDataReceived)
@@ skipping 178 matching lines @@
     return image.release();
 }
 
 bool DeferredImageDecoder::hotSpot(IntPoint& hotSpot) const
 {
     // TODO: Implement.
     return m_actualDecoder ? m_actualDecoder->hotSpot(hotSpot) : false;
 }
 
 } // namespace blink