cc: Do not cleanup tiles with raster tasks.

cc/resources/tile_manager.cc

Index: cc/resources/tile_manager.cc
diff --git a/cc/resources/tile_manager.cc b/cc/resources/tile_manager.cc
index dab3f5562823f5eadbdac2e7d7488726dee14f14..43d211efa5f88403123fb273ac1aa59ba3e048f5 100644
--- a/cc/resources/tile_manager.cc
+++ b/cc/resources/tile_manager.cc
@@ -389,18 +389,18 @@ TileManager::~TileManager() {
   // our memory usage to drop to zero.
   global_state_ = GlobalStateThatImpactsTilePriority();
 
-  CleanUpReleasedTiles();
-  DCHECK_EQ(0u, tiles_.size());
-
   RasterTaskQueue empty;
   rasterizer_->ScheduleTasks(&empty);
-  orphan_raster_tasks_.clear();
 
   // This should finish all pending tasks and release any uninitialized
   // resources.
   rasterizer_->Shutdown();
   rasterizer_->CheckForCompletedTasks();
 
+  FreeResourcesForReleasedTiles();
+  CleanUpReleasedTiles();
+  DCHECK_EQ(0u, tiles_.size());
+
   DCHECK_EQ(0u, bytes_releasable_);
   DCHECK_EQ(0u, resources_releasable_);
 }
@@ -418,18 +418,27 @@ bool TileManager::ShouldForceTasksRequiredForActivationToComplete() const {
   return global_state_.tree_priority != SMOOTHNESS_TAKES_PRIORITY;
 }
 
-void TileManager::CleanUpReleasedTiles() {
+void TileManager::FreeResourcesForReleasedTiles() {
   for (std::vector<Tile*>::iterator it = released_tiles_.begin();
        it != released_tiles_.end();
        ++it) {
     Tile* tile = *it;
-    ManagedTileState& mts = tile->managed_state();
+    FreeResourcesForTile(tile);
+  }
+}
 
-    for (int mode = 0; mode < NUM_RASTER_MODES; ++mode) {
-      FreeResourceForTile(tile, static_cast<RasterMode>(mode));
-      orphan_raster_tasks_.push_back(mts.tile_versions[mode].raster_task_);
+void TileManager::CleanUpReleasedTiles() {
+  DCHECK(prioritized_tiles_dirty_);
+  std::vector<Tile*>::iterator it = released_tiles_.begin();
+  while (it != released_tiles_.end()) {
+    Tile* tile = *it;
+
+    if (tile->HasRasterTask()) {
+      ++it;
+      continue;
     }
 
+    DCHECK(!tile->HasResources());
     DCHECK(tiles_.find(tile->id()) != tiles_.end());
     tiles_.erase(tile->id());
 
@@ -442,15 +451,15 @@ void TileManager::CleanUpReleasedTiles() {
     }
 
     delete tile;
+    it = released_tiles_.erase(it);
   }
-
-  released_tiles_.clear();
 }
 
 void TileManager::UpdatePrioritizedTileSetIfNeeded() {
   if (!prioritized_tiles_dirty_)
     return;
 
+  FreeResourcesForReleasedTiles();
   CleanUpReleasedTiles();
 
   prioritized_tiles_.Clear();
@@ -484,6 +493,8 @@ void TileManager::DidFinishRunningTasks() {
     return;
   }
 
+  FreeResourcesForReleasedTiles();
+
   resource_pool_->ReduceResourceUsage();
 
   // We don't reserve memory for required-for-activation tiles during
@@ -973,11 +984,6 @@ void TileManager::ScheduleTasks(
   // in |raster_tasks_|.
   rasterizer_->ScheduleTasks(&raster_queue_);
 
-  // It's now safe to clean up orphan tasks as raster worker pool is not
-  // allowed to keep around unreferenced raster tasks after ScheduleTasks() has
-  // been called.
-  orphan_raster_tasks_.clear();
-
   did_check_for_completed_tasks_since_last_schedule_tasks_ = false;
 }
 
@@ -1072,17 +1078,12 @@ void TileManager::OnRasterTaskCompleted(
     const PicturePileImpl::Analysis& analysis,
     bool was_canceled) {
   TileMap::iterator it = tiles_.find(tile_id);
-  if (it == tiles_.end()) {
-    ++update_visible_tiles_stats_.canceled_count;
-    resource_pool_->ReleaseResource(resource.Pass());
-    return;
-  }
+  DCHECK(it != tiles_.end());
 
   Tile* tile = it->second;
   ManagedTileState& mts = tile->managed_state();
   ManagedTileState::TileVersion& tile_version = mts.tile_versions[raster_mode];
   DCHECK(tile_version.raster_task_);
-  orphan_raster_tasks_.push_back(tile_version.raster_task_);
   tile_version.raster_task_ = NULL;
 
   if (was_canceled) {