SyncFS: Introduce SyncFileSystemBackend

chrome/browser/media_galleries/fileapi/media_file_system_mount_point_provider.cc

Index: chrome/browser/media_galleries/fileapi/media_file_system_mount_point_provider.cc
diff --git a/chrome/browser/media_galleries/fileapi/media_file_system_mount_point_provider.cc b/chrome/browser/media_galleries/fileapi/media_file_system_mount_point_provider.cc
index 3512e9704c1e3f38ea3426ee16b2f00c642b613c..ab883563b90a15042e98ebe72f76ee01fa5cb863 100644
--- a/chrome/browser/media_galleries/fileapi/media_file_system_mount_point_provider.cc
+++ b/chrome/browser/media_galleries/fileapi/media_file_system_mount_point_provider.cc
@@ -103,6 +103,13 @@ bool MediaFileSystemMountPointProvider::CanHandleType(
   }
 }
 
+GURL MediaFileSystemMountPointProvider::GetRootURI(
+    const GURL& origin_url,
+    fileapi::FileSystemType type) const {
+  NOTIMPLEMENTED();
+  return GURL();
+}
+
 void MediaFileSystemMountPointProvider::OpenFileSystem(
     const GURL& origin_url,
     fileapi::FileSystemType type,
@@ -208,4 +215,11 @@ MediaFileSystemMountPointProvider::GetQuotaUtil() {
   return NULL;
 }
 
+const fileapi::UpdateObserverList*
+MediaFileSystemMountPointProvider::GetUpdateObservers(
+    fileapi::FileSystemType type) const {
+  // No update observer support.
+  return NULL;
+}
+
 }  // namespace chrome