Create Mojo service for locking/unlocking screen orientation.

content/common/screen_orientation_service.mojom

Index: content/common/screen_orientation_service.mojom
diff --git a/content/common/screen_orientation_service.mojom b/content/common/screen_orientation_service.mojom
new file mode 100644
index 0000000000000000000000000000000000000000..8aaadc408dfc3e77e3d4f4088d73b2181ba2504f
--- /dev/null
+++ b/content/common/screen_orientation_service.mojom
@@ -0,0 +1,15 @@
+// Copyright 2014 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.
+
+import "content/public/common/screen_orientation.mojom"
+
+module content {
+
+interface ScreenOrientationService {
+  LockOrientation(ScreenOrientationLockType lock_type) =>
+      (ScreenOrientationLockResult result);
+  UnlockOrientation();
+};
+
+}