FrameSinkIds use to WindowIds in window server, Process ID/Route ID in renderer

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

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef OffscreenCanvasFrameDispatcherImpl_h
 #define OffscreenCanvasFrameDispatcherImpl_h
 
 #include "cc/ipc/mojo_compositor_frame_sink.mojom-blink.h"
 #include "cc/resources/shared_bitmap.h"
 #include "cc/surfaces/surface_id.h"
 #include "mojo/public/cpp/bindings/binding.h"
 #include "platform/graphics/OffscreenCanvasFrameDispatcher.h"
 #include "platform/graphics/StaticBitmapImage.h"
 #include "wtf/Compiler.h"
 #include <memory>
 
 namespace blink {
 
 class PLATFORM_EXPORT OffscreenCanvasFrameDispatcherImpl final
     : public OffscreenCanvasFrameDispatcher,
       WTF_NON_EXPORTED_BASE(
           public cc::mojom::blink::MojoCompositorFrameSinkClient) {
  public:
-  explicit OffscreenCanvasFrameDispatcherImpl(uint32_t clientId,
-                                              uint32_t localId,
-                                              uint64_t nonce,
-                                              int width,
-                                              int height);
+  OffscreenCanvasFrameDispatcherImpl(uint32_t clientId,
+                                     uint32_t sinkId,
+                                     uint32_t localId,
+                                     uint64_t nonce,
+                                     int width,
+                                     int height);
 
   // OffscreenCanvasFrameDispatcher implementation.
   ~OffscreenCanvasFrameDispatcherImpl() override {}
   void dispatchFrame(RefPtr<StaticBitmapImage>) override;
 
   // cc::mojom::blink::MojoCompositorFrameSinkClient implementation.
   void ReturnResources(
       Vector<cc::mojom::blink::ReturnedResourcePtr> resources) override;
 
  private:
   const cc::SurfaceId m_surfaceId;
   const int m_width;
   const int m_height;
 
   unsigned m_nextResourceId;
   unsigned getNextResourceIdAndIncrement() { return m_nextResourceId++; }
   HashMap<unsigned, RefPtr<StaticBitmapImage>> m_cachedImages;
   HashMap<unsigned, std::unique_ptr<cc::SharedBitmap>> m_sharedBitmaps;
 
   bool verifyImageSize(const sk_sp<SkImage>&);
 
   cc::mojom::blink::MojoCompositorFrameSinkPtr m_sink;
   mojo::Binding<cc::mojom::blink::MojoCompositorFrameSinkClient> m_binding;
 };
 
 }  // namespace blink
 
 #endif  // OffscreenCanvasFrameDispatcherImpl_h