Move JoinString to the base namespace

chrome/browser/extensions/unpacked_installer.cc

 // Copyright (c) 2013 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/extensions/unpacked_installer.h"
 
 #include "base/bind.h"
 #include "base/callback.h"
 #include "base/files/file_util.h"
 #include "base/strings/string_util.h"
@@ skipping 233 matching lines @@
 void UnpackedInstaller::OnInstallChecksComplete(int failed_checks) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
 
   if (!install_checker_.policy_error().empty()) {
     ReportExtensionLoadError(install_checker_.policy_error());
     return;
   }
 
   if (!install_checker_.requirement_errors().empty()) {
     ReportExtensionLoadError(
-        JoinString(install_checker_.requirement_errors(), ' '));
+        base::JoinString(install_checker_.requirement_errors(), " "));
     return;
   }
 
   InstallExtension();
 }
 
 int UnpackedInstaller::GetFlags() {
   std::string id = crx_file::id_util::GenerateIdForPath(extension_path_);
   bool allow_file_access =
       Manifest::ShouldAlwaysAllowFileAccess(Manifest::UNPACKED);
@@ skipping 104 matching lines @@
   service_weak_->OnExtensionInstalled(
       extension(), syncer::StringOrdinal(), kInstallFlagInstallImmediately);
 
   if (!callback_.is_null()) {
     callback_.Run(extension(), extension_path_, std::string());
     callback_.Reset();
   }
 }
 
 }  // namespace extensions