Fix screen mirroring on Chrome OS (ReflectorTexture partial swap)

content/browser/compositor/gpu_browser_compositor_output_surface.h

 // Copyright 2014 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_BROWSER_COMPOSITOR_GPU_BROWSER_COMPOSITOR_OUTPUT_SURFACE_H_
 #define CONTENT_BROWSER_COMPOSITOR_GPU_BROWSER_COMPOSITOR_OUTPUT_SURFACE_H_
 
 #include <memory>
 
 #include "base/macros.h"
@@ skipping 68 matching lines @@
   void SetDrawRectangle(const gfx::Rect& rect) override;
 
   // GpuVSyncControl implementation.
   void SetNeedsVSync(bool needs_vsync) override;
 
  protected:
   gpu::CommandBufferProxyImpl* GetCommandBufferProxy();
 
   cc::OutputSurfaceClient* client_ = nullptr;
   std::unique_ptr<ReflectorTexture> reflector_texture_;
+  bool reflector_texture_defined_ = false;
   bool set_draw_rectangle_for_frame_ = false;
   // True if the draw rectangle has been set at all since the last resize.
   bool has_set_draw_rectangle_since_last_resize_ = false;
   gfx::Size size_;
   base::WeakPtrFactory<GpuBrowserCompositorOutputSurface> weak_ptr_factory_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(GpuBrowserCompositorOutputSurface);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_COMPOSITOR_GPU_BROWSER_COMPOSITOR_OUTPUT_SURFACE_H_