[ew] Move operation observers from QuotaUtil to FileSystemBackend.

chrome/browser/chromeos/fileapi/file_system_backend.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/fileapi/file_system_backend.h"
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/stringprintf.h"
 #include "chrome/browser/chromeos/fileapi/file_access_permissions.h"
@@ skipping 127 matching lines @@
   }
 
   callback.Run(GURL(root_url), name, base::File::FILE_OK);
 }
 
 storage::FileSystemQuotaUtil* FileSystemBackend::GetQuotaUtil() {
   // No quota support.
   return NULL;
 }
 
+const storage::UpdateObserverList* FileSystemBackend::GetUpdateObservers(
+    storage::FileSystemType type) const {
+  return NULL;
+}
+
+const storage::ChangeObserverList* FileSystemBackend::GetChangeObservers(
+    storage::FileSystemType type) const {
+  return NULL;
+}
+
+const storage::AccessObserverList* FileSystemBackend::GetAccessObservers(
+    storage::FileSystemType type) const {
+  return NULL;
+}
+
 bool FileSystemBackend::IsAccessAllowed(
     const storage::FileSystemURL& url) const {
   if (!url.is_valid())
     return false;
 
   // No extra check is needed for isolated file systems.
   if (url.mount_type() == storage::kFileSystemTypeIsolated)
     return true;
 
   if (!CanHandleURL(url))
@@ skipping 252 matching lines @@
     case storage::kFileSystemTypeRestrictedNativeLocal:
       callback.Run(GURL());
       return;
     default:
       NOTREACHED();
   }
   callback.Run(GURL());
 }
 
 }  // namespace chromeos