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 92821e0e8852e0f37534c3518a494da5869b3f20..e94fb7caf1040ddd05cbb83b593fdae85c069ba3 100644
--- a/cc/resources/tile_manager.h
+++ b/cc/resources/tile_manager.h
@@ -108,8 +108,7 @@ 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,
@@ -254,7 +253,6 @@ 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_;