Remove SendBeginFramesToChildren plumbing

cc/test/layer_tree_test.cc

Index: cc/test/layer_tree_test.cc
diff --git a/cc/test/layer_tree_test.cc b/cc/test/layer_tree_test.cc
index 87a79debd6b8f21eeb25e8415e153d1057878ae3..e1c6b054fca2caefcca92ac3bcd43655ec1c50b2 100644
--- a/cc/test/layer_tree_test.cc
+++ b/cc/test/layer_tree_test.cc
@@ -371,10 +371,6 @@ class LayerTreeHostClientForTesting : public LayerTreeHostClient,
     test_hooks_->DidInitializeOutputSurface();
   }
 
-  void SendBeginFramesToChildren(const BeginFrameArgs& args) override {
-    test_hooks_->SendBeginFramesToChildren(args);
-  }
-
   void DidFailToInitializeOutputSurface() override {
     test_hooks_->DidFailToInitializeOutputSurface();
     RequestNewOutputSurface();