Reland: Add support for $i18n{} localized strings to ios/web.

ios/web/public/web_ui_ios_data_source.h

 // 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.
 
 #ifndef IOS_WEB_PUBLIC_WEB_UI_IOS_DATA_SOURCE_H_
 #define IOS_WEB_PUBLIC_WEB_UI_IOS_DATA_SOURCE_H_
 
 #include "base/callback.h"
 #include "base/strings/string16.h"
 #include "base/supports_user_data.h"
 
+namespace base {
+class DictionaryValue;
+}
+
 namespace web {
 class BrowserState;
 
 // A data source that can help with implementing the common operations needed by
 // WebUIIOS pages.
 class WebUIIOSDataSource : public base::SupportsUserData {
  public:
   ~WebUIIOSDataSource() override {}
 
   static WebUIIOSDataSource* Create(const std::string& source_name);
 
   // Adds a WebUIIOS data source to |browser_state|.
   static void Add(BrowserState* browser_state, WebUIIOSDataSource* source);
 
   // Adds a string keyed to its name to our dictionary.
   virtual void AddString(const std::string& name,
                          const base::string16& value) = 0;
 
   // Adds a string keyed to its name to our dictionary.
   virtual void AddString(const std::string& name, const std::string& value) = 0;
 
   // Adds a localized string with resource |ids| keyed to its name to our
   // dictionary.
   virtual void AddLocalizedString(const std::string& name, int ids) = 0;
 
+  virtual void AddLocalizedStrings(
+      const base::DictionaryValue& localized_strings) = 0;
+
   // Adds a boolean keyed to its name to our dictionary.
   virtual void AddBoolean(const std::string& name, bool value) = 0;
 
   // Sets the path which will return the JSON strings.
   virtual void SetJsonPath(const std::string& path) = 0;
 
   // Adds a mapping between a path name and a resource to return.
   virtual void AddResourcePath(const std::string& path, int resource_id) = 0;
 
   // Sets the resource to returned when no other paths match.
   virtual void SetDefaultResource(int resource_id) = 0;
 
   // The following map to methods on URLDataSource. See the documentation there.
   virtual void DisableDenyXFrameOptions() = 0;
 };
 
 }  // namespace web
 
 #endif  // IOS_WEB_PUBLIC_WEB_UI_IOS_DATA_SOURCE_H_