Update Native Client Authors to be Chromium Authors for the code moved from the

ppapi/native_client/src/shared/ppapi_proxy/plugin_ppb_var.cc

-// Copyright (c) 2011 The Native Client Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
 #include "native_client/src/shared/ppapi_proxy/plugin_ppb_var.h"
 
 #include <stdio.h>
 
 #include <string>
 #include <utility>
 
@@ skipping 178 matching lines @@
       DebugPrintf("PP_Var(object: %"NACL_PRIu64")", GetVarId(var));
       break;
     case PP_VARTYPE_ARRAY:
     case PP_VARTYPE_DICTIONARY:
       NACL_NOTREACHED();
       break;
   }
 }
 
 }  // namespace ppapi_proxy