Mus: Fixes rendering of transparent containers.

components/mus/ws/platform_display.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 COMPONENTS_MUS_WS_PLATFORM_DISPLAY_H_
 #define COMPONENTS_MUS_WS_PLATFORM_DISPLAY_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 35 matching lines @@
 }  // namespace ui
 
 namespace mus {
 
 class GpuState;
 class SurfacesState;
 class DisplayCompositor;
 
 namespace ws {
 
+namespace test {
+class PlatformDisplayTest;
+}
+
 class EventDispatcher;
 class PlatformDisplayFactory;
 class ServerWindow;
 
 struct ViewportMetrics {
   gfx::Size size_in_pixels;
   float device_scale_factor = 0.f;
 };
 
 // PlatformDisplay is used to connect the root ServerWindow to a display.
@@ skipping 64 matching lines @@
   void SetCursorById(int32_t cursor) override;
   float GetDeviceScaleFactor() override;
   mojom::Rotation GetRotation() override;
   void UpdateTextInputState(const ui::TextInputState& state) override;
   void SetImeVisibility(bool visible) override;
   bool IsFramePending() const override;
   void RequestCopyOfOutput(
       std::unique_ptr<cc::CopyOutputRequest> output_request) override;
   int64_t GetDisplayId() const override;
 
+  void set_delegate_for_testing(PlatformDisplayDelegate* delegate) {
+    delegate_ = delegate;
+  }
+
  private:
+  friend class mus::ws::test::PlatformDisplayTest;

[sky, 2016/06/27 15:17:08]

If you're going to friend this, then don't bother with the set function.

[mfomitchev, 2016/06/30 22:06:03]

Done.

+
   void WantToDraw();
 
   // This method initiates a top level redraw of the display.
   // TODO(fsamuel): This should use vblank as a signal rather than a timer
   // http://crbug.com/533042
   void Draw();
 
   // This is called after cc::Display has completed generating a new frame
   // for the display. TODO(fsamuel): Idle time processing should happen here
   // if there is budget for it.
@@ skipping 35 matching lines @@
   base::WeakPtrFactory<DefaultPlatformDisplay> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DefaultPlatformDisplay);
 };
 
 }  // namespace ws
 
 }  // namespace mus
 
 #endif  // COMPONENTS_MUS_WS_PLATFORM_DISPLAY_H_