HDR: Do nonlinear blending in the compositor

cc/surfaces/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 CC_SURFACES_DISPLAY_H_
 #define CC_SURFACES_DISPLAY_H_
 
 #include <memory>
 #include <vector>
 
@@ skipping 52 matching lines @@
 
   ~Display() override;
 
   void Initialize(DisplayClient* client, SurfaceManager* surface_manager);
 
   // device_scale_factor is used to communicate to the external window system
   // what scale this was rendered at.
   void SetLocalSurfaceId(const LocalSurfaceId& id, float device_scale_factor);
   void SetVisible(bool visible);
   void Resize(const gfx::Size& new_size);
-  void SetColorSpace(const gfx::ColorSpace& color_space);
+  void SetColorSpace(const gfx::ColorSpace& blending_color_space,
+                     const gfx::ColorSpace& device_color_space);
   void SetOutputIsSecure(bool secure);
 
   const SurfaceId& CurrentSurfaceId();
 
   // DisplaySchedulerClient implementation.
   bool DrawAndSwap() override;
 
   // OutputSurfaceClient implementation.
   void SetNeedsRedrawRect(const gfx::Rect& damage_rect) override;
   void DidReceiveSwapBuffersAck() override;
@@ skipping 17 matching lines @@
   SharedBitmapManager* const bitmap_manager_;
   gpu::GpuMemoryBufferManager* const gpu_memory_buffer_manager_;
   const RendererSettings settings_;
 
   DisplayClient* client_ = nullptr;
   SurfaceManager* surface_manager_ = nullptr;
   const FrameSinkId frame_sink_id_;
   SurfaceId current_surface_id_;
   gfx::Size current_surface_size_;
   float device_scale_factor_ = 1.f;
+  gfx::ColorSpace blending_color_space_;
   gfx::ColorSpace device_color_space_;
   bool visible_ = false;
   bool swapped_since_resize_ = false;
   bool output_is_secure_ = false;
 
   // The begin_frame_source_ is not owned here, and also often known by the
   // output_surface_ and the scheduler_.
   BeginFrameSource* begin_frame_source_;
   std::unique_ptr<OutputSurface> output_surface_;
   std::unique_ptr<DisplayScheduler> scheduler_;
   std::unique_ptr<ResourceProvider> resource_provider_;
   std::unique_ptr<SurfaceAggregator> aggregator_;
   std::unique_ptr<TextureMailboxDeleter> texture_mailbox_deleter_;
   std::unique_ptr<DirectRenderer> renderer_;
   SoftwareRenderer* software_renderer_ = nullptr;
   std::vector<ui::LatencyInfo> stored_latency_info_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(Display);
 };
 
 }  // namespace cc
 
 #endif  // CC_SURFACES_DISPLAY_H_