Multiple sync channels if used in the same listener thread could result in ca...

ipc/ipc_sync_message_unittest.h

Index: ipc/ipc_sync_message_unittest.h
===================================================================
--- ipc/ipc_sync_message_unittest.h	(revision 28676)
+++ ipc/ipc_sync_message_unittest.h	(working copy)
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include <string>
+
 #include "ipc/ipc_message_macros.h"
 
 IPC_BEGIN_MESSAGES(Test)
@@ -14,6 +16,9 @@
                               int /* in */,
                               int /* out */)
 
+  IPC_SYNC_MESSAGE_CONTROL0_1(SyncChannelNestedTestMsg_String,
+                              std::string)
+
   // out1 is false
   IPC_SYNC_MESSAGE_CONTROL0_1(Msg_C_0_1, bool)