Only allow subsequence caching for SVG documents, not inline SVG.

third_party/WebKit/Source/core/svg/graphics/SVGImage.h

 /*
  * Copyright (C) 2006 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2009 Apple 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
@@ skipping 165 matching lines @@
                                PaintFlags&,
                                const SkMatrix& local_matrix);
   bool ApplyShaderInternal(PaintFlags&,
                            const SkMatrix& local_matrix,
                            const KURL&);
 
   void StopAnimation();
   void ScheduleTimelineRewind();
   void FlushPendingTimelineRewind();
 
+  Page* GetPage() { return page_; }

[fs, 2017/05/17 11:14:45]

Nit: GetPageForTesting to avoid given people wrong ideas.

[chrishtr, 2017/05/17 17:01:18]

Done.

   void LoadCompleted();
 
   class SVGImageLocalFrameClient;
 
   Persistent<SVGImageChromeClient> chrome_client_;
   Persistent<Page> page_;
   std::unique_ptr<PaintController> paint_controller_;
 
   // When an SVG image has no intrinsic size, the size depends on the default
   // object size, which in turn depends on the container. One SVGImage may
   // belong to multiple containers so the final image size can't be known in
   // SVGImage. SVGImageForContainer carries the final image size, also called
   // the "concrete object size". For more, see: SVGImageForContainer.h
   IntSize intrinsic_size_;
   bool has_pending_timeline_rewind_;
 
   enum LoadState {
     kDataChangedNotStarted,
     kInDataChanged,
     kWaitingForAsyncLoadCompletion,
     kLoadCompleted,
   };
 
   LoadState load_state_ = kDataChangedNotStarted;
 
   Persistent<SVGImageLocalFrameClient> frame_client_;
+  FRIEND_TEST_ALL_PREFIXES(SVGImageTest, SupportsSubsequenceCaching);
 };
 
 DEFINE_IMAGE_TYPE_CASTS(SVGImage);
 
 class ImageObserverDisabler {
   STACK_ALLOCATED();
   WTF_MAKE_NONCOPYABLE(ImageObserverDisabler);
 
  public:
   ImageObserverDisabler(Image* image) : image_(image) {
     image_->SetImageObserverDisabled(true);
   }
 
   ~ImageObserverDisabler() { image_->SetImageObserverDisabled(false); }
 
  private:
   Image* image_;
 };
 
 }  // namespace blink
 
 #endif  // SVGImage_h