Android: Remove unneeded RegisterNatives() calls

chrome/browser/android/signin/signin_promo_util_android.h

 // 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.
 
 #ifndef CHROME_BROWSER_ANDROID_SIGNIN_SIGNIN_PROMO_UTIL_ANDROID_H_
 #define CHROME_BROWSER_ANDROID_SIGNIN_SIGNIN_PROMO_UTIL_ANDROID_H_
 
 #include "base/android/jni_android.h"
 #include "components/signin/core/browser/signin_metrics.h"
 #include "content/public/browser/android/content_view_core.h"
 
 namespace chrome {
 namespace android {
 
 class SigninPromoUtilAndroid {
  public:
   // Opens a signin flow with the specified |access_point| for metrics within
   // the context of |content_view_core|, which could be null.
   static void StartAccountSigninActivityForPromo(
       content::ContentViewCore* content_view_core,
       signin_metrics::AccessPoint access_point);
-
-  static bool Register(JNIEnv* env);
 };
 
 }  // namespace android
 }  // namespace chrome
 
 #endif  // CHROME_BROWSER_ANDROID_SIGNIN_SIGNIN_PROMO_UTIL_ANDROID_H_