Add an Ioctl() message to the File interface.

services/files/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 "services/files/file_impl.h"
 
 #include <errno.h>
 #include <fcntl.h>
 #include <sys/stat.h>
 #include <sys/types.h>
@@ skipping 300 matching lines @@
   if (!file_fd_.is_valid()) {
     callback.Run(ERROR_CLOSED, ScopedSharedBufferHandle());
     return;
   }
 
   // TODO(vtl): FIXME soon
   NOTIMPLEMENTED();
   callback.Run(ERROR_UNIMPLEMENTED, ScopedSharedBufferHandle());
 }
 
+void FileImpl::Ioctl(uint32_t request,
+                     Array<uint32_t> in_values,
+                     const IoctlCallback& callback) {
+  if (!file_fd_.is_valid()) {
+    callback.Run(ERROR_CLOSED, Array<uint32_t>());
+    return;
+  }
+
+  // TODO(vtl): The "correct" error code should be one that can be translated to
+  // ENOTTY!
+  callback.Run(ERROR_UNAVAILABLE, Array<uint32_t>());
+}
+
 }  // namespace files
 }  // namespace mojo