Move JoinString to the base namespace

extensions/renderer/print_native_handler.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 "extensions/renderer/print_native_handler.h"
 
 #include <string>
 
 #include "base/bind.h"
 #include "base/strings/string_util.h"
 
 namespace extensions {
 
 PrintNativeHandler::PrintNativeHandler(ScriptContext* context)
     : ObjectBackedNativeHandler(context) {
   RouteFunction("Print",
                 base::Bind(&PrintNativeHandler::Print, base::Unretained(this)));
 }
 
 void PrintNativeHandler::Print(
     const v8::FunctionCallbackInfo<v8::Value>& args) {
   if (args.Length() < 1)
     return;
 
   std::vector<std::string> components;
   for (int i = 0; i < args.Length(); ++i)
     components.push_back(*v8::String::Utf8Value(args[i]));
 
-  LOG(ERROR) << JoinString(components, ',');
+  LOG(ERROR) << base::JoinString(components, ",");
 }
 
 }  // namespace extensions