Add base:: to string16 in extensions/.

extensions/common/manifest.cc

 // Copyright 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 "extensions/common/manifest.h"
 
 #include "base/basictypes.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/strings/string_split.h"
@@ skipping 189 matching lines @@
     const std::string& path, int* out_value) const {
   return CanAccessPath(path) && value_->GetInteger(path, out_value);
 }
 
 bool Manifest::GetString(
     const std::string& path, std::string* out_value) const {
   return CanAccessPath(path) && value_->GetString(path, out_value);
 }
 
 bool Manifest::GetString(
-    const std::string& path, string16* out_value) const {
+    const std::string& path, base::string16* out_value) const {
   return CanAccessPath(path) && value_->GetString(path, out_value);
 }
 
 bool Manifest::GetDictionary(
     const std::string& path, const base::DictionaryValue** out_value) const {
   return CanAccessPath(path) && value_->GetDictionary(path, out_value);
 }
 
 bool Manifest::GetList(
     const std::string& path, const base::ListValue** out_value) const {
@@ skipping 36 matching lines @@
   Feature* feature = FeatureProvider::GetManifestFeatures()->GetFeature(key);
   if (!feature)
     return true;
 
   return feature->IsAvailableToManifest(
       extension_id_, type_, Feature::ConvertLocation(location_),
       GetManifestVersion()).is_available();
 }
 
 }  // namespace extensions