cc: Change max_tiles_for_interest_rect to be screen pixels padding.

cc/trees/layer_tree_settings.h

Index: cc/trees/layer_tree_settings.h
diff --git a/cc/trees/layer_tree_settings.h b/cc/trees/layer_tree_settings.h
index 6334f94bb1311e681dfc91b1d11b8068a98dd150..cc98747bbf223b10edf45c6521334e9463d81bb6 100644
--- a/cc/trees/layer_tree_settings.h
+++ b/cc/trees/layer_tree_settings.h
@@ -67,7 +67,7 @@ class CC_EXPORT LayerTreeSettings {
   gfx::Size max_untiled_layer_size;
   gfx::Size default_tile_grid_size;
   gfx::Size minimum_occlusion_tracking_size;
-  size_t max_tiles_for_interest_area;
+  size_t tiling_interest_area_padding;
   float skewport_target_time_in_seconds;
   int skewport_extrapolation_limit_in_content_pixels;
   size_t max_unused_resource_memory_percentage;