Move //mojo/services/X/public/... to //mojo/services/X/... (part 2).

mojo/services/gpu/public/interfaces/context_provider.mojom

-// 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.
-
-[DartPackage="mojo_services"]
-module mojo;
-
-import "gpu/public/interfaces/command_buffer.mojom";
-import "gpu/public/interfaces/viewport_parameter_listener.mojom";
-
-// A ContextProvider can be used to provide new command buffers related to a
-// particular context, for instance configured to draw to a particular display.
-interface ContextProvider {
-  // This initializes a new command buffer for this provider when available,
-  // closing connections to the previously created command buffer (if any).
-  //
-  // This call may not return for an extended period of time if a command
-  // buffer cannot be produced immediately, for example if it is associated
-  // with a view that is offscreen.
-  //
-  // If a viewport_parameter_listener is provided it will notified be when
-  // vsync parameters change for this context.
-  //
-  // The returned handle will be null if no command buffer can be created for
-  // this request, for example if another request is made on the same provider
-  // before a previous call returns.
-  Create(ViewportParameterListener? viewport_parameter_listener)
-      => (CommandBuffer? gles2_client);
-};