cc: Optimize decode scheduling for checker-images.

cc/tiles/tile_draw_info.h

 // Copyright 2013 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_TILES_TILE_DRAW_INFO_H_
 #define CC_TILES_TILE_DRAW_INFO_H_
 
 #include <memory>
 
 #include "base/trace_event/trace_event_argument.h"
@@ skipping 59 matching lines @@
   bool requires_resource() const {
     return mode_ == RESOURCE_MODE || mode_ == OOM_MODE;
   }
 
   inline bool has_resource() const { return !!resource_; }
 
   inline bool has_compressed_resource() const {
     return resource_ ? IsResourceFormatCompressed(resource_->format()) : false;
   }
 
+  bool is_checker_imaged() const {
+    DCHECK(!resource_is_checker_imaged_ || resource_);
+    return resource_is_checker_imaged_;
+  }
+
   void SetSolidColorForTesting(SkColor color) { set_solid_color(color); }
 
   void AsValueInto(base::trace_event::TracedValue* state) const;
 
  private:
   friend class Tile;
   friend class TileManager;
 
   const Resource* resource() const { return resource_; }
 
-  void set_resource(Resource* resource) {
+  void set_resource(Resource* resource, bool resource_is_checker_imaged) {

[vmpstr, 2017/04/18 00:20:00]

You could just make false the default value.

[Khushal, 2017/04/19 06:16:41]

Do we have default values for arguments? I never noticed it in chromium code.

+    DCHECK(!resource_is_checker_imaged || resource)
+        << "Need to have a resource for it to be checker-imaged";
+
     mode_ = RESOURCE_MODE;
     is_resource_ready_to_draw_ = false;
+    resource_is_checker_imaged_ = resource_is_checker_imaged;
     resource_ = resource;
   }
 
   void set_resource_ready_for_draw() {
     is_resource_ready_to_draw_ = true;
   }
 
   Resource* TakeResource();
 
   void set_solid_color(const SkColor& color) {
     mode_ = SOLID_COLOR_MODE;
     solid_color_ = color;
   }
 
   void set_oom() { mode_ = OOM_MODE; }
 
   Mode mode_ = RESOURCE_MODE;
   SkColor solid_color_ = SK_ColorWHITE;
   Resource* resource_ = nullptr;
   bool contents_swizzled_ = false;
   bool is_resource_ready_to_draw_ = false;
+
+  // Set to true if |resource_| was rasterized with checker-imaged content. The
+  // flag can only be true iff we have a valid |resource_|.
+  bool resource_is_checker_imaged_ = false;
 };
 
 }  // namespace cc
 
 #endif  // CC_TILES_TILE_DRAW_INFO_H_