gpu: Replace GpuMsg_GpuSwitched with mojom api.

services/ui/gpu/interfaces/gpu_service.mojom

 // Copyright 2016 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.
 
 module ui.mojom;
 
 import "cc/ipc/display_compositor.mojom";
 import "gpu/ipc/common/gpu_info.mojom";
 import "gpu/ipc/common/memory_stats.mojom";
 import "gpu/ipc/common/surface_handle.mojom";
@@ skipping 32 matching lines @@
 
   // Notify GPU that a shader was loaded from disk.
   LoadedShader(string data);
 
   // Tells GPU to release the surface because it's being destroyed.
   DestroyingVideoSurface(int32 surface_id) => ();
 
   // Tells GPU to wake up the GPU because we're about to draw.
   WakeUpGpu();
 
+  // Tells GPU that host has seen a GPU switch. This can happen when the display
+  // is reconfigured, for example.
+  GpuSwitched();
+
   DestroyAllChannels();
 
   Crash();
   Hang();
   ThrowJavaException();
   Stop() => ();
 };