Fix screen mirroring on Chrome OS (ReflectorTexture partial swap)

content/browser/compositor/gpu_browser_compositor_output_surface.h

Index: content/browser/compositor/gpu_browser_compositor_output_surface.h
diff --git a/content/browser/compositor/gpu_browser_compositor_output_surface.h b/content/browser/compositor/gpu_browser_compositor_output_surface.h
index 1212ccd0e2739d53d19024b7145659bdf7935bc5..8d12eb15eaf34bfd75f1c5954d68bb6f0a2e22a1 100644
--- a/content/browser/compositor/gpu_browser_compositor_output_surface.h
+++ b/content/browser/compositor/gpu_browser_compositor_output_surface.h
@@ -86,6 +86,7 @@ class GpuBrowserCompositorOutputSurface : public BrowserCompositorOutputSurface,
 
   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;