Update from https://crrev.com/309717

tools/clang/blink_gc_plugin/tests/traceimpl.cpp

Index: tools/clang/blink_gc_plugin/tests/traceimpl.cpp
diff --git a/tools/clang/blink_gc_plugin/tests/traceimpl.cpp b/tools/clang/blink_gc_plugin/tests/traceimpl.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..61d8560ea68f37523d416622eb2ee2d11991bd7a
--- /dev/null
+++ b/tools/clang/blink_gc_plugin/tests/traceimpl.cpp
@@ -0,0 +1,17 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "traceimpl.h"
+
+namespace blink {
+
+void TraceImplExtern::trace(Visitor* visitor) {
+  traceImpl(visitor);
+}
+
+template <typename VisitorDispatcher>
+inline void TraceImplExtern::traceImpl(VisitorDispatcher visitor) {
+  visitor->trace(m_x);
+}
+}