ProtectorService supports multiple change instances.

chrome/browser/protector/settings_change_global_error.h

Index: chrome/browser/protector/settings_change_global_error.h
diff --git a/chrome/browser/protector/settings_change_global_error.h b/chrome/browser/protector/settings_change_global_error.h
index d7db869af3bbafd6c1a05d8955eb13947ad0c705..1c893563368230480343f70f047fd57430f1fe60 100644
--- a/chrome/browser/protector/settings_change_global_error.h
+++ b/chrome/browser/protector/settings_change_global_error.h
@@ -10,6 +10,7 @@
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
+#include "chrome/app/chrome_command_ids.h"
 #include "chrome/browser/protector/base_setting_change.h"
 #include "chrome/browser/ui/browser_list.h"
 #include "chrome/browser/ui/global_error.h"
@@ -40,6 +41,9 @@ class SettingsChangeGlobalError : public GlobalError,
   // Removes global error from its profile.
   void RemoveFromProfile();
 
+  // Returns the change instance to which this error refers.
+  BaseSettingChange* change() { return change_; }
+
  private:
   // GlobalError implementation.
   virtual bool HasBadge() OVERRIDE;
@@ -97,6 +101,9 @@ class SettingsChangeGlobalError : public GlobalError,
 
   base::WeakPtrFactory<SettingsChangeGlobalError> weak_factory_;
 
+  // Menu command ID assigned to |this| from the pool of available IDs.
+  int menu_id_;
+
   DISALLOW_COPY_AND_ASSIGN(SettingsChangeGlobalError);
 };