SetNeedsRedraw directly when updating a visible tile.

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 f5bea383141a38c325f695ed2247e9b7561331a9..68fc8ebab11cddb3d347c27bd820849fd13f76a4 100644
--- a/cc/resources/tile_manager.h
+++ b/cc/resources/tile_manager.h
@@ -104,8 +104,7 @@ class CC_EXPORT TileManager : public RasterizerClient,
 
   void ManageTiles(const GlobalStateThatImpactsTilePriority& state);
 
-  // Returns true when visible tiles have been initialized.
-  bool UpdateVisibleTiles();
+  void UpdateVisibleTiles();
 
   scoped_refptr<Tile> CreateTile(RasterSource* raster_source,
                                  const gfx::Size& tile_size,
@@ -248,7 +247,6 @@ class CC_EXPORT TileManager : public RasterizerClient,
 
   RenderingStatsInstrumentation* rendering_stats_instrumentation_;
 
-  bool did_initialize_visible_tile_;
   bool did_check_for_completed_tasks_since_last_schedule_tasks_;
   bool did_oom_on_last_assign_;