Exclude host-side code from the NaCl IRT proxy build.

ppapi/proxy/ppb_file_ref_proxy.cc

Index: ppapi/proxy/ppb_file_ref_proxy.cc
===================================================================
--- ppapi/proxy/ppb_file_ref_proxy.cc	(revision 161336)
+++ ppapi/proxy/ppb_file_ref_proxy.cc	(working copy)
@@ -192,6 +192,7 @@
 bool PPB_FileRef_Proxy::OnMessageReceived(const IPC::Message& msg) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(PPB_FileRef_Proxy, msg)
+#if !defined(OS_NACL)
     IPC_MESSAGE_HANDLER(PpapiHostMsg_PPBFileRef_Create, OnMsgCreate)
     IPC_MESSAGE_HANDLER(PpapiHostMsg_PPBFileRef_GetParent, OnMsgGetParent)
     IPC_MESSAGE_HANDLER(PpapiHostMsg_PPBFileRef_MakeDirectory,
@@ -201,6 +202,7 @@
     IPC_MESSAGE_HANDLER(PpapiHostMsg_PPBFileRef_Rename, OnMsgRename)
     IPC_MESSAGE_HANDLER(PpapiHostMsg_PPBFileRef_GetAbsolutePath,
                         OnMsgGetAbsolutePath)
+#endif  // !defined(OS_NACL)
 
     IPC_MESSAGE_HANDLER(PpapiMsg_PPBFileRef_CallbackComplete,
                         OnMsgCallbackComplete)
@@ -225,6 +227,7 @@
   return (new FileRef(serialized))->GetReference();
 }
 
+#if !defined(OS_NACL)
 void PPB_FileRef_Proxy::OnMsgCreate(const HostResource& file_system,
                                     const std::string& path,
                                     PPB_FileRef_CreateInfo* result) {
@@ -297,6 +300,7 @@
   if (enter.succeeded())
     result.Return(dispatcher(), enter.object()->GetAbsolutePath());
 }
+#endif  // !defined(OS_NACL)
 
 void PPB_FileRef_Proxy::OnMsgCallbackComplete(
     const HostResource& host_resource,
@@ -308,6 +312,7 @@
     static_cast<FileRef*>(enter.object())->ExecuteCallback(callback_id, result);
 }
 
+#if !defined(OS_NACL)
 void PPB_FileRef_Proxy::OnCallbackCompleteInHost(
     int32_t result,
     const HostResource& host_resource,
@@ -316,6 +321,7 @@
   Send(new PpapiMsg_PPBFileRef_CallbackComplete(
       API_ID_PPB_FILE_REF, host_resource, callback_id, result));
 }
+#endif  // !defined(OS_NACL)
 
 }  // namespace proxy
 }  // namespace ppapi