Reland (2): cc: Make tile manager object persist for the length of LTHI.

cc/tiles/tile_manager.h

Index: cc/tiles/tile_manager.h
diff --git a/cc/tiles/tile_manager.h b/cc/tiles/tile_manager.h
index 56ec94b58b3114e6460ee94b32ffe331a4192535..332699fad39587d43fc239b9c76c5adbf607e611 100644
--- a/cc/tiles/tile_manager.h
+++ b/cc/tiles/tile_manager.h
@@ -106,8 +106,6 @@ class CC_EXPORT TileManager : public TileTaskRunnerClient {
 
   static scoped_ptr<TileManager> Create(TileManagerClient* client,
                                         base::SequencedTaskRunner* task_runner,
-                                        ResourcePool* resource_pool,
-                                        TileTaskRunner* tile_task_runner,
                                         size_t scheduled_raster_task_limit);
   ~TileManager() override;
 
@@ -116,7 +114,16 @@ class CC_EXPORT TileManager : public TileTaskRunnerClient {
   // activation are prepared, or failed to prepare due to OOM.
   // - Runs client_->NotifyReadyToDraw() when all tiles required draw are
   // prepared, or failed to prepare due to OOM.
-  void PrepareTiles(const GlobalStateThatImpactsTilePriority& state);
+  bool PrepareTiles(const GlobalStateThatImpactsTilePriority& state);
+
+  // Synchronously finish any in progress work, cancel the rest, and clean up as
+  // much resources as possible. Also, prevents any future work until a
+  // SetResources call.
+  void FinishTasksAndCleanUp();
+
+  // Set the new given resource pool and tile task runner.

[enne (OOO), 2015/07/06 18:07:25]

Should you leave a comment here that you need to call FinishTasksAndCleanUp
before calling this a second time? Or should that happen automatically in
SetResources rather than DCHECKing?

[vmpstr, 2015/07/06 18:41:35]

In order to ensure that the caller is aware that FinishTasksAndCleanUp is
happening, I'd prefer to do the comment route instead of an implicit call to it.
Added the comment.

+  void SetResources(ResourcePool* resource_pool,
+                    TileTaskRunner* tile_task_runner);
 
   // This causes any completed raster work to finalize, so that tiles get up to
   // date draw information.
@@ -196,8 +203,6 @@ class CC_EXPORT TileManager : public TileTaskRunnerClient {
  protected:
   TileManager(TileManagerClient* client,
               const scoped_refptr<base::SequencedTaskRunner>& task_runner,
-              ResourcePool* resource_pool,
-              TileTaskRunner* tile_task_runner,
               size_t scheduled_raster_task_limit);
 
   void FreeResourcesForReleasedTiles();