Stub out initial NavigationController browser implementation

content/common/nav_controller/nav_controller_messages.h

Index: content/common/nav_controller/nav_controller_messages.h
diff --git a/content/common/nav_controller/nav_controller_messages.h b/content/common/nav_controller/nav_controller_messages.h
new file mode 100644
index 0000000000000000000000000000000000000000..d0acf0104b89a9a6f5561d3c953f23e2fdc3e873
--- /dev/null
+++ b/content/common/nav_controller/nav_controller_messages.h
@@ -0,0 +1,27 @@
+// Copyright (c) 2013 The Chromium Authors. All rights reserved.

[jam, 2013/09/13 22:44:40]

nit: ipc files have owners that are only security folks. so this file can just
be in content/common (I'm assuming you put it in a subdir for owners reasons)

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Message definition file, included multiple times, hence no include guard.
+
+#include "base/strings/string16.h"
+#include "ipc/ipc_message_macros.h"
+#include "ipc/ipc_param_traits.h"
+#include "url/gurl.h"
+
+#define IPC_MESSAGE_START NavControllerMsgStart
+
+IPC_MESSAGE_CONTROL3(NavControllerHostMsg_RegisterController,
+                     int32 /* host_id */,
+                     string16 /* scope */,
+                     GURL /* script_url */)
+
+IPC_MESSAGE_CONTROL1(NavControllerMsg_ControllerReady, int32 /* host_id */)
+
+IPC_MESSAGE_CONTROL2(NavControllerHostMsg_UnregisterController,
+                     int32 /* host_id */,
+                     string16 /* scope */)
+
+IPC_MESSAGE_CONTROL2(NavControllerMsg_ControllerUnregistered,
+                     int32 /* host_id */,
+                     string16 /* scope */)