Make more services' public interfaces flexible wrt location in repo.

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

 // 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.
 
 module mojo;
 
-import "mojo/services/gpu/public/interfaces/gpu_capabilities.mojom";
+import "gpu/public/interfaces/gpu_capabilities.mojom";
 
 struct CommandBufferState {
   int32 num_entries;
   int32 get_offset;
   int32 put_offset;
   int32 token;
   int32 error;  // TODO(piman): enum
   int32 context_lost_reason;  // TODO(piman): enum
   uint32 generation;
 };
@@ skipping 26 matching lines @@
   RetireSyncPoint(uint32 sync_point);
   Echo() => ();
 
   // TODO(piman): sync points
 };
 
 interface CommandBufferClient {
   DidDestroy();
   LostContext(int32 lost_reason);  // TODO(piman): enum
 };