Remove the default format from ResourcePool.

cc/resources/tile_manager.h

Index: cc/resources/tile_manager.h
diff --git a/cc/resources/tile_manager.h b/cc/resources/tile_manager.h
index cdab9e69cb69fc8f39a70f2bac68dca74264a0cc..8deaba8e2e1c8ea2f22d61f86316bd8970209cee 100644
--- a/cc/resources/tile_manager.h
+++ b/cc/resources/tile_manager.h
@@ -137,9 +137,9 @@ class CC_EXPORT TileManager : public TileTaskRunnerClient,
   void InitializeTilesWithResourcesForTesting(const std::vector<Tile*>& tiles) {
     for (size_t i = 0; i < tiles.size(); ++i) {
       TileDrawInfo& draw_info = tiles[i]->draw_info();
-      draw_info.resource_ =
-          resource_pool_->AcquireResource(tiles[i]->desired_texture_size(),
-                                          resource_pool_->default_format());
+      draw_info.resource_ = resource_pool_->AcquireResource(
+          tiles[i]->desired_texture_size(),
+          tile_task_runner_->GetResourceFormat());
     }
   }
 
@@ -291,8 +291,6 @@ class CC_EXPORT TileManager : public TileTaskRunnerClient,
 
   std::vector<Tile*> released_tiles_;
 
-  ResourceFormat resource_format_;
-
   // Queue used when scheduling raster tasks.
   TileTaskQueue raster_queue_;