Use a direct include of strings headers in chrome/common/, part 1.

chrome/common/extensions/manifest_handlers/app_isolation_info.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/common/extensions/manifest_handlers/app_isolation_info.h"
 
 #include "base/memory/scoped_ptr.h"
-#include "base/string16.h"
+#include "base/strings/string16.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
 #include "chrome/common/extensions/extension_manifest_constants.h"
 #include "chrome/common/extensions/permissions/api_permission_set.h"
 #include "chrome/common/extensions/permissions/permissions_data.h"
 #include "extensions/common/error_utils.h"
 
 namespace keys = extension_manifest_keys;
 
@@ skipping 70 matching lines @@
 
 bool AppIsolationHandler::AlwaysParseForType(Manifest::Type type) const {
   return type == Manifest::TYPE_PLATFORM_APP;
 }
 
 const std::vector<std::string> AppIsolationHandler::Keys() const {
   return SingleKey(keys::kIsolation);
 }
 
 }  // namespace extensions