blink: Fix frame completion querying for static images.

third_party/WebKit/Source/platform/image-decoders/ImageDecoder.h

 /*
  * Copyright (C) 2006 Apple Computer, Inc.  All rights reserved.
  * Copyright (C) Research In Motion Limited 2009-2010. 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
@@ skipping 175 matching lines @@
   virtual int RepetitionCount() const { return kCAnimationNone; }
 
   // Decodes as much of the requested frame as possible, and returns an
   // ImageDecoder-owned pointer.
   ImageFrame* FrameBufferAtIndex(size_t);
 
   // Whether the requested frame has alpha.
   virtual bool FrameHasAlphaAtIndex(size_t) const;
 
   // Whether or not the frame is fully received.
   virtual bool FrameIsCompleteAtIndex(size_t) const;

[scroggo_chromium, 2017/05/30 15:51:34]

nit: As a follow-on, I think we should rename this to FrameIsReceivedAtIndex.
This old name is confusing.

[scroggo_chromium, 2017/07/17 19:25:35]

Uploaded crrev.com/2982083002

 
+  // Returns true if a cached complete decode is available.
+  bool FrameIsDecodedAtIndex(size_t) const;
+
   // Duration for displaying a frame in milliseconds. This method is only used
   // by animated images.
   virtual float FrameDurationAtIndex(size_t) const { return 0; }
 
   // Number of bytes in the decoded frame. Returns 0 if the decoder doesn't
   // have this frame cached (either because it hasn't been decoded, or because
   // it has been cleared).
   virtual size_t FrameBytesAtIndex(size_t) const;
 
   ImageOrientation Orientation() const { return orientation_; }
@@ skipping 220 matching lines @@
   bool has_histogrammed_color_space_ = false;
 
   sk_sp<SkColorSpace> embedded_color_space_ = nullptr;
   bool source_to_target_color_transform_needs_update_ = false;
   std::unique_ptr<SkColorSpaceXform> source_to_target_color_transform_;
 };
 
 }  // namespace blink
 
 #endif