cc: Remove memory state from tile management

cc/resources/managed_tile_state.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_RESOURCES_MANAGED_TILE_STATE_H_
 #define CC_RESOURCES_MANAGED_TILE_STATE_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "cc/resources/platform_color.h"
 #include "cc/resources/raster_worker_pool.h"
 #include "cc/resources/resource_pool.h"
 #include "cc/resources/resource_provider.h"
 #include "cc/resources/tile_manager.h"
 
 namespace cc {
 
-enum TileVersionMemoryState {
-  NOT_ALLOWED_TO_USE_MEMORY,
-  CAN_USE_MEMORY,
-  USING_UNRELEASABLE_MEMORY,
-  USING_RELEASABLE_MEMORY
-};
-
 // This is state that is specific to a tile that is
 // managed by the TileManager.
 class CC_EXPORT ManagedTileState {
  public:
   class CC_EXPORT TileVersion {
     public:
       enum Mode {
         RESOURCE_MODE,
         SOLID_COLOR_MODE,
         PICTURE_PILE_MODE,
         NUM_MODES
       };
 
       TileVersion();
       ~TileVersion();
 
       Mode mode() const {
         return mode_;
       }
 
       bool IsReadyToDraw() const;
 
       ResourceProvider::ResourceId get_resource_id() const {
         DCHECK(mode_ == RESOURCE_MODE);
+
+        // We have to have a resource ID here.
         DCHECK(resource_id_);
-        DCHECK(memory_state_ == USING_RELEASABLE_MEMORY || forced_upload_);
+        // If we have a resource, it implies IDs are equal.
+        DCHECK(!resource_ || (resource_id_ == resource_->id()));
+        // If we don't have a resource, it implies that we're in forced upload.
+        DCHECK(resource_ || (resource_id_ && forced_upload_));
+
         return resource_id_;
       }
 
       SkColor get_solid_color() const {
         DCHECK(mode_ == SOLID_COLOR_MODE);
 
         return solid_color_;
       }
 
       bool contents_swizzled() const {
         return !PlatformColor::SameComponentOrder(resource_format_);
       }
 
       bool requires_resource() const {
         return mode_ == RESOURCE_MODE ||
                mode_ == PICTURE_PILE_MODE;
       }
 
       size_t GPUMemoryUsageInBytes() const;
 
       void SetResourceForTesting(scoped_ptr<ResourcePool::Resource> resource) {
         resource_ = resource.Pass();
         resource_id_ = resource_->id();
       }
 
       scoped_ptr<ResourcePool::Resource>& GetResourceForTesting() {
         return resource_;
       }
 
-      void SetMemoryStateForTesting(TileVersionMemoryState state) {
-        memory_state_ = state;
-      }
-
     private:
       friend class TileManager;
       friend class Tile;
       friend class ManagedTileState;
 
       void set_use_resource() {
         mode_ = RESOURCE_MODE;
-        if (memory_state_ == NOT_ALLOWED_TO_USE_MEMORY)
-          memory_state_ = CAN_USE_MEMORY;
       }
 
       void set_solid_color(const SkColor& color) {
         mode_ = SOLID_COLOR_MODE;
         solid_color_ = color;
-        memory_state_ = NOT_ALLOWED_TO_USE_MEMORY;
         resource_id_ = 0;
       }
 
       void set_rasterize_on_demand() {
         mode_ = PICTURE_PILE_MODE;
-        memory_state_ = NOT_ALLOWED_TO_USE_MEMORY;
         resource_id_ = 0;
       }
 
       Mode mode_;
       SkColor solid_color_;
 
       // TODO(reveman): Eliminate the need for both |resource_id_|
       // and |resource| by re-factoring the "force upload"
       // mechanism. crbug.com/245767
       ResourceProvider::ResourceId resource_id_;
       scoped_ptr<ResourcePool::Resource> resource_;
       GLenum resource_format_;
-      TileVersionMemoryState memory_state_;
       bool forced_upload_;
   };
 
 
   ManagedTileState();
   ~ManagedTileState();
 
   scoped_ptr<base::Value> AsValue() const;
 
   // Persisted state: valid all the time.
@@ skipping 21 matching lines @@
   TileManagerBin gpu_memmgr_stats_bin;
   TileResolution resolution;
   bool required_for_activation;
   float time_to_needed_in_seconds;
   float distance_to_visible_in_pixels;
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_MANAGED_TILE_STATE_H_