Remove DartPackage annotation from NativeViewport and GPU mojoms

mojo/services/gpu/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.
 
-[DartPackage="mojo_services"]
 module mojo;
 
 import "gpu/interfaces/gpu_capabilities.mojom";
 
 struct CommandBufferState {
   int32 num_entries;
   int32 get_offset;
   int32 put_offset;
   int32 token;
   int32 error;  // TODO(piman): enum
@@ skipping 31 matching lines @@
       int32 id, handle<shared_buffer> transfer_buffer, uint32 size);
   DestroyTransferBuffer(int32 id);
 
   // InsertSyncPoint returns the sync point returned via DidInsertSyncPoint.
   // If |retire| is true, the sync point is retired on insertion. Otherwise,
   // explicitly call RetireSyncPoint to retire it.
   InsertSyncPoint(bool retire);
   RetireSyncPoint(uint32 sync_point);
   Echo() => ();
 };