cc: Optimize decode scheduling for checker-images.

cc/test/test_layer_tree_host_base.cc

Index: cc/test/test_layer_tree_host_base.cc
diff --git a/cc/test/test_layer_tree_host_base.cc b/cc/test/test_layer_tree_host_base.cc
index 35fcfadb6fa23b62bc0b311105b831df403007a3..68f9f9b9e719902bd0b7cc103459c546d4fa94b5 100644
--- a/cc/test/test_layer_tree_host_base.cc
+++ b/cc/test/test_layer_tree_host_base.cc
@@ -159,6 +159,18 @@ void TestLayerTreeHostBase::ActivateTree() {
   host_impl()->active_tree()->UpdateDrawProperties(update_lcd_text);
 }
 
+void TestLayerTreeHostBase::PerformImplSideInvalidation() {
+  DCHECK(host_impl()->active_tree());
+  DCHECK(!host_impl()->pending_tree());
+  DCHECK(host_impl()->recycle_tree());
+
+  host_impl()->CreatePendingTree();
+  host_impl()->sync_tree()->InvalidateRegionForImages(
+      host_impl()->tile_manager()->TakeImagesToInvalidateOnSyncTree());
+  pending_layer_ = old_pending_layer_;
+  old_pending_layer_ = nullptr;
+}
+
 void TestLayerTreeHostBase::RebuildPropertyTreesOnPendingTree() {
   host_impl()->pending_tree()->property_trees()->needs_rebuild = true;
   host_impl()->pending_tree()->BuildLayerListAndPropertyTreesForTesting();