Removing the use of base::Time inside the LayerTreeHost system.

cc/trees/layer_tree_impl.cc

Index: cc/trees/layer_tree_impl.cc
diff --git a/cc/trees/layer_tree_impl.cc b/cc/trees/layer_tree_impl.cc
index d7e41075c6fb7ed8710ef5773a099ab8bd3ecaf0..6a66a2d6d224d09f7152950567b5c0ec5ab53050 100644
--- a/cc/trees/layer_tree_impl.cc
+++ b/cc/trees/layer_tree_impl.cc
@@ -684,10 +684,6 @@ base::TimeTicks LayerTreeImpl::CurrentFrameTimeTicks() const {
   return layer_tree_host_impl_->CurrentFrameTimeTicks();
 }
 
-base::Time LayerTreeImpl::CurrentFrameTime() const {
-  return layer_tree_host_impl_->CurrentFrameTime();
-}
-
 base::TimeTicks LayerTreeImpl::CurrentPhysicalTimeTicks() const {
   return layer_tree_host_impl_->CurrentPhysicalTimeTicks();
 }