Add stable id to PaintImage.

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

 /*
  * Copyright (c) 2008, Google Inc. All rights reserved.
  * Copyright (C) 2009 Dirk Schulze <krit@webkit.org>
  * Copyright (C) 2010 Torch Mobile (Beijing) Co. Ltd. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
@@ skipping 506 matching lines @@
     return;
 
   if (surface->IsRecording()) {
     // Using a GPU-backed image with RecordingImageBufferSurface
     // will fail at playback time.
     image = image->makeNonTextureImage();
   }
   // TODO(vmpstr): Figure out actual values for this.
   auto animation_type = PaintImage::AnimationType::UNKNOWN;
   auto completion_state = PaintImage::CompletionState::UNKNOWN;
-  surface->Canvas()->drawImage(
-      PaintImage(std::move(image), animation_type, completion_state), 0, 0);
+  static PaintImage::Id unknown_stable_id = PaintImage::GetNextId();
+  surface->Canvas()->drawImage(PaintImage(unknown_stable_id, std::move(image),
+                                          animation_type, completion_state),
+                               0, 0);
 
   surface->SetImageBuffer(this);
   if (client_)
     client_->RestoreCanvasMatrixClipStack(surface->Canvas());
   surface_ = std::move(surface);
 
   UpdateGPUMemoryUsage();
 }
 
 void ImageBuffer::SetNeedsCompositingUpdate() {
@@ skipping 27 matching lines @@
   DCHECK(MIMETypeRegistry::IsSupportedImageMIMETypeForEncoding(mime_type));
 
   Vector<unsigned char> result;
   if (!EncodeImage(mime_type, quality, &result))
     return "data:,";
 
   return "data:" + mime_type + ";base64," + Base64Encode(result);
 }
 
 }  // namespace blink