cc : Make CallFunctionForSubtree on impl use layer iterator

BUG=568817
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel

Review URL: https://codereview.chromium.org/1846043002

Cr-Commit-Position: refs/heads/master@{#384630}
diff --git a/cc/trees/tree_synchronizer_unittest.cc b/cc/trees/tree_synchronizer_unittest.cc
index 4b958de..f625cca 100644
--- a/cc/trees/tree_synchronizer_unittest.cc
+++ b/cc/trees/tree_synchronizer_unittest.cc
@@ -21,6 +21,7 @@
 #include "cc/test/fake_rendering_stats_instrumentation.h"
 #include "cc/test/test_shared_bitmap_manager.h"
 #include "cc/test/test_task_graph_runner.h"
+#include "cc/trees/layer_tree_host_common.h"
 #include "cc/trees/single_thread_proxy.h"
 #include "cc/trees/task_runner_provider.h"
 #include "testing/gtest/include/gtest/gtest.h"