MD Settings: Convert C++ handlers to be JavaScript-lifecycle aware.

chrome/browser/ui/webui/settings/search_engines_handler.h

Index: chrome/browser/ui/webui/settings/search_engines_handler.h
diff --git a/chrome/browser/ui/webui/settings/search_engines_handler.h b/chrome/browser/ui/webui/settings/search_engines_handler.h
index d5a11c8093d87cd8d2bdb3649c234fd2e0d3f542..650ac84d4b74e80040c4f29845a9788d8e54c91a 100644
--- a/chrome/browser/ui/webui/settings/search_engines_handler.h
+++ b/chrome/browser/ui/webui/settings/search_engines_handler.h
@@ -9,10 +9,10 @@
 
 #include "base/macros.h"
 #include "chrome/browser/ui/search_engines/edit_search_engine_controller.h"
+#include "chrome/browser/ui/search_engines/keyword_editor_controller.h"
 #include "chrome/browser/ui/webui/settings/settings_page_ui_handler.h"
 #include "ui/base/models/table_model_observer.h"
 
-class KeywordEditorController;
 class Profile;
 
 namespace extensions {
@@ -40,12 +40,12 @@ class SearchEnginesHandler : public SettingsPageUIHandler,
                        const base::string16& keyword,
                        const std::string& url) override;
 
+  // SettingsPageUIHandler implementation.
   void RegisterMessages() override;
+  void OnJavascriptAllowed() override;
+  void OnJavascriptDisallowed() override;
 
  private:
-  std::unique_ptr<KeywordEditorController> list_controller_;
-  std::unique_ptr<EditSearchEngineController> edit_controller_;
-
   // Retrieves all search engines and returns the to WebUI.
   void HandleGetSearchEnginesList(const base::ListValue* args);
 
@@ -91,6 +91,9 @@ class SearchEnginesHandler : public SettingsPageUIHandler,
 
   Profile* const profile_;
 
+  KeywordEditorController list_controller_;
+  std::unique_ptr<EditSearchEngineController> edit_controller_;
+
   DISALLOW_COPY_AND_ASSIGN(SearchEnginesHandler);
 };