mandoline filesystem: add a sqlite3 vfs to proxy filesystem usage.

components/filesystem/file_impl.cc

 // Copyright 2015 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 "components/filesystem/file_impl.h"
 
 #include <stdint.h>
 #include <limits>
 
 #include "base/files/file_path.h"
@@ skipping 242 matching lines @@
   if (!new_file.IsValid()) {
     callback.Run(GetError(new_file));
     return;
   }
 
   if (file.is_pending())
     new FileImpl(file.Pass(), new_file.Pass());
   callback.Run(FILE_ERROR_OK);
 }
 
+void FileImpl::Flush(const FlushCallback& callback) {
+  if (!file_.IsValid()) {
+    callback.Run(GetError(file_));
+    return;
+  }
+
+  bool ret = file_.Flush();
+  callback.Run(ret ? FILE_ERROR_OK : FILE_ERROR_FAILED);
+}
+
 void FileImpl::AsHandle(const AsHandleCallback& callback) {
   if (!file_.IsValid()) {
     callback.Run(GetError(file_), ScopedHandle());
     return;
   }
 
   base::File new_file = file_.Duplicate();
   if (!new_file.IsValid()) {
     callback.Run(GetError(new_file), ScopedHandle());
     return;
@@ skipping 19 matching lines @@
       new_file.TakePlatformFile(), &mojo_handle);
   if (create_result != MOJO_RESULT_OK) {
     callback.Run(FILE_ERROR_FAILED, ScopedHandle());
     return;
   }
 
   callback.Run(FILE_ERROR_OK, ScopedHandle(mojo::Handle(mojo_handle)).Pass());
 }
 
 }  // namespace filesystem