android_webview: Remove unneeded RegisterNatives() calls

android_webview/native/aw_contents_io_thread_client_impl.cc

 // Copyright (c) 2012 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 "android_webview/native/aw_contents_io_thread_client_impl.h"
 
 #include <map>
 #include <memory>
 #include <utility>
 
@@ skipping 518 matching lines @@
       web_request.jstringArray_header_names.obj(),
       web_request.jstringArray_header_values.obj(),
       jstring_mime_type.obj(),
       jstring_encoding.obj(),
       status_code,
       jstring_reason.obj(),
       jstringArray_response_header_names.obj(),
       jstringArray_response_header_values.obj());
 }
 
-bool RegisterAwContentsIoThreadClientImpl(JNIEnv* env) {
-  return RegisterNativesImpl(env);
-}
-
 } // namespace android_webview