[fsp] Add an option for mounting in R/W mode.

chrome/browser/chromeos/extensions/file_system_provider/file_system_provider_api.cc

 // Copyright 2013 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 "chrome/browser/chromeos/extensions/file_system_provider/file_system_provider_api.h"
 
 #include <string>
 
 #include "base/debug/trace_event.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 34 matching lines @@
   }
 
   Service* service = Service::Get(GetProfile());
   DCHECK(service);
   if (!service)
     return false;
 
   // TODO(mtomasz): Pass more detailed errors, rather than just a bool.
   if (!service->MountFileSystem(extension_id(),
                                 params->options.file_system_id,
-                                params->options.display_name)) {
+                                params->options.display_name,
+                                params->options.writable)) {
     base::ListValue* result = new base::ListValue();
     result->Append(CreateError(kSecurityErrorName, kMountFailedErrorMessage));
     SetResult(result);
     return true;
   }
 
   base::ListValue* result = new base::ListValue();
   SetResult(result);
   return true;
 }
@@ skipping 87 matching lines @@
   using api::file_system_provider_internal::OperationRequestedError::Params;
   scoped_ptr<Params> params(Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params);
 
   const base::File::Error error = ProviderErrorToFileError(params->error);
   RejectRequest(RequestValue::CreateForOperationError(params.Pass()), error);
   return true;
 }
 
 }  // namespace extensions