Implement the file chooser as a new resource "host"

ppapi/proxy/ppb_file_ref_proxy.cc

 // Copyright (c) 2012 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 "ppapi/proxy/ppb_file_ref_proxy.h"
 
 #include <map>
 
 #include "base/bind.h"
 #include "ppapi/c/pp_errors.h"
@@ skipping 216 matching lines @@
     IPC_MESSAGE_HANDLER(PpapiHostMsg_PPBFileRef_GetAbsolutePath,
                         OnMsgGetAbsolutePath)
 
     IPC_MESSAGE_HANDLER(PpapiMsg_PPBFileRef_CallbackComplete,
                         OnMsgCallbackComplete)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
   return handled;
 }
 
+// static
 void PPB_FileRef_Proxy::SerializeFileRef(PP_Resource file_ref,
                                          PPB_FileRef_CreateInfo* result) {
   EnterResourceNoLock<PPB_FileRef_API> enter(file_ref, false);
   if (enter.succeeded())
     *result = enter.object()->GetCreateInfo();
 }
 
 // static
 PP_Resource PPB_FileRef_Proxy::DeserializeFileRef(
     const PPB_FileRef_CreateInfo& serialized) {
@@ skipping 89 matching lines @@
     int32_t result,
     const HostResource& host_resource,
     int callback_id) {
   // Execute OnMsgCallbackComplete in the plugin process.
   Send(new PpapiMsg_PPBFileRef_CallbackComplete(
       API_ID_PPB_FILE_REF, host_resource, callback_id, result));
 }
 
 }  // namespace proxy
 }  // namespace ppapi