Add stream operator for SurfaceId/FrameSinkId/LocalFrameId.

cc/surfaces/local_frame_id.cc

Index: cc/surfaces/local_frame_id.cc
diff --git a/cc/surfaces/local_frame_id.cc b/cc/surfaces/local_frame_id.cc
new file mode 100644
index 0000000000000000000000000000000000000000..b92ac8a6b7de73dab7855403700aa19a811d7212
--- /dev/null
+++ b/cc/surfaces/local_frame_id.cc
@@ -0,0 +1,21 @@
+// Copyright 2016 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 "cc/surfaces/local_frame_id.h"
+
+#include "base/strings/stringprintf.h"
+
+namespace cc {
+
+std::string LocalFrameId::ToString() const {
+  return base::StringPrintf("LocalFrameId(%d, %s" PRIu64 ")", local_id_,
+                            nonce_.ToString().c_str());
+}
+
+std::ostream& operator<<(std::ostream& out,
+                         const LocalFrameId& local_frame_id) {
+  return out << local_frame_id.ToString();
+}
+
+}  // namespace cc