cc: Add command line switch to control resource usage for impl-side painting.

cc/trees/layer_tree_settings.cc

Index: cc/trees/layer_tree_settings.cc
diff --git a/cc/trees/layer_tree_settings.cc b/cc/trees/layer_tree_settings.cc
index 2969ae58fdf3a503f7d892e8ac8874131f61944e..757ab4af78c709fefd8932af316aa599d97b662d 100644
--- a/cc/trees/layer_tree_settings.cc
+++ b/cc/trees/layer_tree_settings.cc
@@ -50,7 +50,8 @@ LayerTreeSettings::LayerTreeSettings()
       use_pinch_zoom_scrollbars(false),
       max_prepaint_tile_distance(4096),
       // At 256x256 tiles, 128 tiles cover an area of 2048x4096 pixels.
-      max_tiles_for_interest_area(128) {
+      max_tiles_for_interest_area(128),
+      max_unused_resource_memory_percentage(100) {
   // TODO(danakj): Renable surface caching when we can do it more realiably.
   // crbug.com/170713
   cache_render_pass_contents = false;