Enforce constant size and device scale factor for surfaces

content/renderer/android/synchronous_compositor_frame_sink.h

 // Copyright 2013 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 CONTENT_RENDERER_ANDROID_SYNCHRONOUS_COMPOSITOR_FRAME_SINK_H_
 #define CONTENT_RENDERER_ANDROID_SYNCHRONOUS_COMPOSITOR_FRAME_SINK_H_
 
 #include <stddef.h>
 
 #include <memory>
@@ skipping 138 matching lines @@
         const cc::RenderPassList& render_passes) override {}
     void DisplayDidDrawAndSwap() override {}
   };
 
   // TODO(danakj): These don't to be stored in unique_ptrs when OutputSurface
   // is owned/destroyed on the compositor thread.
   std::unique_ptr<cc::SurfaceManager> surface_manager_;
   std::unique_ptr<cc::LocalSurfaceIdAllocator> local_surface_id_allocator_;
   cc::LocalSurfaceId child_local_surface_id_;
   cc::LocalSurfaceId root_local_surface_id_;
+  gfx::Size child_size_;
+  gfx::Size display_size_;
+  float device_scale_factor_ = 0;
   // Uses surface_manager_.
   std::unique_ptr<cc::CompositorFrameSinkSupport> root_support_;
   // Uses surface_manager_.
   std::unique_ptr<cc::CompositorFrameSinkSupport> child_support_;
   StubDisplayClient display_client_;
   // Uses surface_manager_.
   std::unique_ptr<cc::Display> display_;
   // Owned by |display_|.
   SoftwareOutputSurface* software_output_surface_ = nullptr;
   std::unique_ptr<cc::BeginFrameSource> begin_frame_source_;
 
   gfx::Rect sw_viewport_for_current_draw_;
 
   base::ThreadChecker thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(SynchronousCompositorFrameSink);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_ANDROID_SYNCHRONOUS_COMPOSITOR_FRAME_SINK_H_