Avoid element id collisions with the visual viewport

third_party/WebKit/Source/platform/graphics/GraphicsLayer.h

 /*
  * Copyright (C) 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Intel Corporation. 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 248 matching lines @@
   std::unique_ptr<base::trace_event::ConvertableToTraceFormat> TakeDebugInfo(
       cc::Layer*) override;
   void didUpdateMainThreadScrollingReasons() override;
 
   PaintController& getPaintController();
 
   // Exposed for tests.
   WebLayer* contentsLayer() const { return m_contentsLayer; }
 
   void setElementId(const CompositorElementId&);
+  CompositorElementId elementId() const;
+
   void setCompositorMutableProperties(uint32_t);
 
   ContentLayerDelegate* contentLayerDelegateForTesting() const {
     return m_contentLayerDelegate.get();
   }
 
   // DisplayItemClient methods
   String debugName() const final { return m_client->debugName(this); }
   LayoutRect visualRect() const override;
 
@@ skipping 119 matching lines @@
 };
 
 }  // namespace blink
 
 #ifndef NDEBUG
 // Outside the blink namespace for ease of invocation from gdb.
 void PLATFORM_EXPORT showGraphicsLayerTree(const blink::GraphicsLayer*);
 #endif
 
 #endif  // GraphicsLayer_h