Move native_viewport.mojom into public/interfaces

mojo/services/native_viewport/native_viewport.mojom

-// 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.
-
-import "../gles2/command_buffer.mojom"
-import "../public/interfaces/geometry/geometry.mojom"
-import "../public/interfaces/input_events/input_events.mojom"
-
-module mojo {
-
-[Client=NativeViewportClient]
-interface NativeViewport {
-  Create(Rect bounds);
-  Show();
-  Hide();
-  Close();
-  SetBounds(Rect bounds);
-  CreateGLES2Context(CommandBuffer& gles2_client);
-};
-
-interface NativeViewportClient {
-  OnCreated();
-  OnBoundsChanged(Rect bounds);
-  OnDestroyed();
-  OnEvent(Event event) => ();
-};
-
-}