Animated PNG implementation

third_party/WebKit/Source/platform/image-decoders/png/PNGImageDecoder.h

Index: third_party/WebKit/Source/platform/image-decoders/png/PNGImageDecoder.h
diff --git a/third_party/WebKit/Source/platform/image-decoders/png/PNGImageDecoder.h b/third_party/WebKit/Source/platform/image-decoders/png/PNGImageDecoder.h
index 7ce6aa0faf83c7c6d2ece1ce6cc94ea5d07f7427..fb12ac0cb62037269817fa2c46be66fa7be47dce 100644
--- a/third_party/WebKit/Source/platform/image-decoders/png/PNGImageDecoder.h
+++ b/third_party/WebKit/Source/platform/image-decoders/png/PNGImageDecoder.h
@@ -45,6 +45,10 @@ class PLATFORM_EXPORT PNGImageDecoder final : public ImageDecoder {
 
   // ImageDecoder:
   String filenameExtension() const override { return "png"; }
+  bool frameIsCompleteAtIndex(size_t) const override;
+  float frameDurationAtIndex(size_t) const override;
+  int repetitionCount() const override;
+  size_t clearCacheExceptFrame(size_t) override;
 
   // Callbacks from libpng
   void headerAvailable();
@@ -53,16 +57,17 @@ class PLATFORM_EXPORT PNGImageDecoder final : public ImageDecoder {
 
  private:
   // ImageDecoder:
-  void decodeSize() override { decode(true); }
-  void decode(size_t) override { decode(false); }
+  void decodeSize() override { parse(); }
+  void decode(size_t) override;
+  size_t decodeFrameCount() override;
+  void initializeNewFrame(size_t) override;
 
-  // Decodes the image.  If |onlySize| is true, stops decoding after
-  // calculating the image size.  If decoding fails but there is no more
-  // data coming, sets the "decode failure" flag.
-  void decode(bool onlySize);
+  bool initFrameBuffer();
+  bool parse();
 
   std::unique_ptr<PNGImageReader> m_reader;
-  const unsigned m_offset;
+  const size_t m_offset;
+  size_t m_currentFrame;
 };
 
 }  // namespace blink