Also delete plugin data when the cookies checkbox in the clear browsing data dialog is checked.

chrome/browser/dom_ui/options/clear_browser_data_handler.h

Index: chrome/browser/dom_ui/options/clear_browser_data_handler.h
diff --git a/chrome/browser/dom_ui/options/clear_browser_data_handler.h b/chrome/browser/dom_ui/options/clear_browser_data_handler.h
index 7789bffb3851c6f9a8aad1da983bc201e434a00c..960fe78b91c5ab65bda0a28e1d3b986ae870064e 100644
--- a/chrome/browser/dom_ui/options/clear_browser_data_handler.h
+++ b/chrome/browser/dom_ui/options/clear_browser_data_handler.h
@@ -8,6 +8,7 @@
 
 #include "chrome/browser/dom_ui/options/options_ui.h"
 #include "chrome/browser/browsing_data_remover.h"
+#include "chrome/browser/plugin_data_remover_helper.h"
 
 // Clear browser data handler page UI handler.
 class ClearBrowserDataHandler : public OptionsPageUIHandler,
@@ -17,14 +18,25 @@ class ClearBrowserDataHandler : public OptionsPageUIHandler,
   virtual ~ClearBrowserDataHandler();
 
   // OptionsUIHandler implementation.
+  virtual void Initialize();
+
   virtual void GetLocalizedValues(DictionaryValue* localized_strings);
 
   // DOMMessageHandler implementation.
   virtual void RegisterMessages();
 
+  // NotificationObserver implementation.
+  virtual void Observe(NotificationType type,
+                       const NotificationSource& source,
+                       const NotificationDetails& details);
+
  private:
+  // Javascript callback to start clearing data.
   void HandleClearBrowserData(const ListValue* value);
 
+  // Updates the UI to reflect whether clearing LSO data is supported.
+  void UpdateClearPluginLSOData();
+
   // Callback from BrowsingDataRemover. Closes the dialog.
   virtual void OnBrowsingDataRemoverDone();
 
@@ -32,6 +44,10 @@ class ClearBrowserDataHandler : public OptionsPageUIHandler,
   // of deleting itself when done.
   BrowsingDataRemover* remover_;
 
+  // Used for asynchronously updating the preference stating whether clearing
+  // LSO data is supported.
+  PluginDataRemoverHelper clear_plugin_lso_data_enabled_;
+
   DISALLOW_COPY_AND_ASSIGN(ClearBrowserDataHandler);
 };