Add base:: namespace to string16 in chrome/browser/extensions.

chrome/browser/extensions/suspicious_extension_bubble_controller.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/suspicious_extension_bubble_controller.h"
 
 #include "base/bind.h"
 #include "base/metrics/histogram.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/extensions/extension_message_bubble.h"
@@ skipping 104 matching lines @@
 SuspiciousExtensionBubbleController::GetLearnMoreLabel() const {
   return l10n_util::GetStringUTF16(IDS_LEARN_MORE);
 }
 
 GURL SuspiciousExtensionBubbleController::GetLearnMoreUrl() const {
   return GURL(chrome::kRemoveNonCWSExtensionURL);
 }
 
 base::string16
 SuspiciousExtensionBubbleController::GetActionButtonLabel() const {
-  return string16();
+  return base::string16();
 }
 
 base::string16
 SuspiciousExtensionBubbleController::GetDismissButtonLabel() const {
   return l10n_util::GetStringUTF16(IDS_EXTENSIONS_SUSPICIOUS_DISABLED_BUTTON);
 }
 
 bool
 SuspiciousExtensionBubbleController::ShouldShowExtensionList() const {
   return true;
 }
 
-std::vector<string16>
+std::vector<base::string16>
 SuspiciousExtensionBubbleController::GetExtensions() {
   return GetExtensionList();
 }
 
 void SuspiciousExtensionBubbleController::LogExtensionCount(
     size_t count) {
   UMA_HISTOGRAM_COUNTS_100(
       "ExtensionWipeoutBubble.ExtensionWipeoutCount", count);
 }
 
 void SuspiciousExtensionBubbleController::LogAction(
     ExtensionMessageBubbleController::BubbleAction action) {
   UMA_HISTOGRAM_ENUMERATION(
       "ExtensionWipeoutBubble.UserSelection",
       action, ExtensionMessageBubbleController::ACTION_BOUNDARY);
 }
 
 template <>
 void ProfileKeyedAPIFactory<
     SuspiciousExtensionBubbleController>::DeclareFactoryDependencies() {
   DependsOn(extensions::ExtensionSystemFactory::GetInstance());
 }
 
 }  // namespace extensions