Remove image_decode_tasks_enabled flag.

cc/layers/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_LAYERS_RECORDING_SOURCE_H_
 #define CC_LAYERS_RECORDING_SOURCE_H_
 
 #include <stddef.h>
 
 #include <memory>
@@ skipping 28 matching lines @@
   virtual ~RecordingSource();
 
   bool UpdateAndExpandInvalidation(Region* invalidation,
                                    const gfx::Size& layer_size,
                                    const gfx::Rect& new_recorded_viewport);
   void UpdateDisplayItemList(const scoped_refptr<DisplayItemList>& display_list,
                              const size_t& painter_reported_memory_usage);
   gfx::Size GetSize() const;
   void SetEmptyBounds();
   void SetSlowdownRasterScaleFactor(int factor);
-  void SetGenerateDiscardableImagesMetadata(bool generate_metadata);
   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;
 
   const DisplayItemList* GetDisplayItemList();
   gfx::Rect recorded_viewport() const { return recorded_viewport_; }
 
  protected:
   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_;
 
  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_LAYERS_RECORDING_SOURCE_H_