Make IPC::Channel::Listener:OnMessageReceived have a return value indicating ...

ppapi/proxy/ppb_url_request_info_proxy.cc

Index: ppapi/proxy/ppb_url_request_info_proxy.cc
===================================================================
--- ppapi/proxy/ppb_url_request_info_proxy.cc	(revision 70108)
+++ ppapi/proxy/ppb_url_request_info_proxy.cc	(working copy)
@@ -111,7 +111,8 @@
   return INTERFACE_ID_PPB_URL_REQUEST_INFO;
 }
 
-void PPB_URLRequestInfo_Proxy::OnMessageReceived(const IPC::Message& msg) {
+bool PPB_URLRequestInfo_Proxy::OnMessageReceived(const IPC::Message& msg) {
+  bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(PPB_URLRequestInfo_Proxy, msg)
     IPC_MESSAGE_HANDLER(PpapiHostMsg_PPBURLRequestInfo_Create, OnMsgCreate)
     IPC_MESSAGE_HANDLER(PpapiHostMsg_PPBURLRequestInfo_SetProperty,
@@ -120,8 +121,10 @@
                         OnMsgAppendDataToBody)
     IPC_MESSAGE_HANDLER(PpapiHostMsg_PPBURLRequestInfo_AppendFileToBody,
                         OnMsgAppendFileToBody)
+    IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   // TODO(brettw): handle bad messages.
+  return handled;
 }
 
 void PPB_URLRequestInfo_Proxy::OnMsgCreate(