cc: Clean up RecordingSource API

cc/playback/recording_source.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_PLAYBACK_RECORDING_SOURCE_H_
 #define CC_PLAYBACK_RECORDING_SOURCE_H_
 
 #include <stddef.h>
 
 #include <memory>
@@ skipping 52 matching lines @@
   void SetBackgroundColor(SkColor background_color);
   void SetRequiresClear(bool requires_clear);
 
   void SetNeedsDisplayRect(const gfx::Rect& layer_rect);
 
   // These functions are virtual for testing.
   virtual scoped_refptr<RasterSource> CreateRasterSource(
       bool can_use_lcd_text) const;
   virtual bool IsSuitableForGpuRasterization() const;
 
-  gfx::Rect recorded_viewport() const { return recorded_viewport_; }
+  gfx::Rect recorded_viewport() const { return inputs_.recorded_viewport; }
 
   const DisplayItemList* GetDisplayItemList();
 
  protected:
   void Clear();
 
-  gfx::Rect recorded_viewport_;
   gfx::Size size_;
   int slow_down_raster_scale_factor_for_debug_;
   bool generate_discardable_images_metadata_;
   bool requires_clear_;
   bool is_solid_color_;
   bool clear_canvas_with_debug_color_;
   SkColor solid_color_;
   SkColor background_color_;
 
-  scoped_refptr<DisplayItemList> display_list_;
-  size_t painter_reported_memory_usage_;
+  // Encapsulates all data received from the ContentLayerClient.
+  struct Inputs {
+    Inputs();

[Khushal, 2016/07/12 23:28:19]

You can inline the initialization and remove the ctor/dtor.

[Menglin, 2016/07/12 23:36:47]

that's what i did but got the "Complex class/struct needs an explicit
out-of-line constructor" when compiling...

[danakj, 2016/07/12 23:39:42]

Then you can inline the initialization and just = default them in the .cc file.

+    ~Inputs();
+
+    gfx::Rect recorded_viewport;
+    scoped_refptr<DisplayItemList> display_list;
+    size_t painter_reported_memory_usage;
+  };
+
+  Inputs inputs_;
 
  private:
   void UpdateInvalidationForNewViewport(const gfx::Rect& old_recorded_viewport,
                                         const gfx::Rect& new_recorded_viewport,
                                         Region* invalidation);
   void FinishDisplayItemListUpdate();
 
   friend class RasterSource;
 
   void DetermineIfSolidColor();
 
   InvalidationRegion invalidation_;
 
   DISALLOW_COPY_AND_ASSIGN(RecordingSource);
 };
 
 }  // namespace cc
 
 #endif  // CC_PLAYBACK_RECORDING_SOURCE_H_