Revert of Move JoinString to the base namespace

chrome/browser/android/preferences/pref_service_bridge.cc

 // 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.
 
 #include "chrome/browser/android/preferences/pref_service_bridge.h"
 
 #include <jni.h>
 
 #include "base/android/build_info.h"
 #include "base/android/jni_android.h"
@@ skipping 817 matching lines @@
   if (accept_languages->find(language_region) == std::string::npos) {
     std::vector<std::string> parts;
     parts.push_back(language_region);
     // If language is not in the accept languages list, also add language code.
     if (accept_languages->find(language + ",") == std::string::npos &&
         !std::equal(language.rbegin(), language.rend(),
                     accept_languages->rbegin())) {
       parts.push_back(language);
     }
     parts.push_back(*accept_languages);
-    *accept_languages = base::JoinString(parts, ",");
+    *accept_languages = JoinString(parts, ',');
   }
 }
 
 // static
 std::string PrefServiceBridge::GetAndroidPermissionForContentSetting(
     ContentSettingsType content_type) {
   JNIEnv* env = AttachCurrentThread();
   base::android::ScopedJavaLocalRef<jstring> android_permission =
       Java_PrefServiceBridge_getAndroidPermissionForContentSetting(
           env, content_type);
   if (android_permission.is_null())
     return std::string();
 
   return ConvertJavaStringToUTF8(android_permission);
 }