Checking if frame is complete and access duration doesn't need a decode

Source/core/platform/image-decoders/ImageDecoder.h

 /*
  * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.
  * Copyright (C) 2008-2009 Torch Mobile, Inc.
  * Copyright (C) Research In Motion Limited 2009-2010. All rights reserved.
  * Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies)
  *
  * 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
@@ skipping 275 matching lines @@
 
         virtual int repetitionCount() const { return cAnimationNone; }
 
         // Decodes as much of the requested frame as possible, and returns an
         // ImageDecoder-owned pointer.
         virtual ImageFrame* frameBufferAtIndex(size_t) = 0;
 
         // Make the best effort guess to check if the requested frame has alpha channel.
         virtual bool frameHasAlphaAtIndex(size_t) const;
 
+        // Whether or not the frame is fully received.
+        virtual bool frameIsCompleteAtIndex(size_t) const;
+
+        // Duration for displaying a frame in seconds. This method is used by animated images only.
+        virtual float frameDurationAtIndex(size_t) const { return 0; }
+
         // Number of bytes in the decoded frame requested. Return 0 if not yet decoded.
         virtual unsigned frameBytesAtIndex(size_t) const;
 
         void setIgnoreGammaAndColorProfile(bool flag) { m_ignoreGammaAndColorProfile = flag; }
         bool ignoresGammaAndColorProfile() const { return m_ignoreGammaAndColorProfile; }
 
         ImageOrientation orientation() const { return m_orientation; }
 
         enum { iccColorProfileHeaderLength = 128 };
 
@@ skipping 115 matching lines @@
         IntSize m_size;
         bool m_sizeAvailable;
         int m_maxNumPixels;
         bool m_isAllDataReceived;
         bool m_failed;
     };
 
 } // namespace WebCore
 
 #endif