Instant: Don't allow the page to set suggestions inappropriately.

chrome/browser/ui/search/instant_controller.h

 // Copyright 2012 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 CHROME_BROWSER_UI_SEARCH_INSTANT_CONTROLLER_H_
 #define CHROME_BROWSER_UI_SEARCH_INSTANT_CONTROLLER_H_
 
 #include <list>
 #include <map>
 #include <string>
@@ skipping 380 matching lines @@
   // In non-extended mode, only |overlay_| is ever non-NULL.
   scoped_ptr<InstantOverlay> overlay_;
   scoped_ptr<InstantNTP> ntp_;
   scoped_ptr<InstantTab> instant_tab_;
 
   // The most recent full_text passed to Update(). If empty, we'll not accept
   // search suggestions from |overlay_| or |instant_tab_|.
   string16 last_omnibox_text_;
 
   // The most recent user_text passed to Update(). Used to filter out-of-date
-  // URL suggestions from the Instant page.
+  // URL suggestions from the Instant page. Set in Update() and cleared when
+  // the page sets temporary text (SetSuggestions() with REPLACE behavior).
   string16 last_user_text_;
 
   // True if the last Update() had an inline autocompletion. Used only to make
   // sure that we don't accidentally suggest gray text suggestion in that case.
   bool last_omnibox_text_has_inline_autocompletion_;
 
   // The most recent verbatim passed to Update(). Used only to ensure that we
   // don't accidentally suggest an inline autocompletion.
   bool last_verbatim_;
 
@@ skipping 57 matching lines @@
   // Used for Top Sites async retrieval.
   base::WeakPtrFactory<InstantController> weak_ptr_factory_;
 
   // Used to get notifications about Most Visted changes.
   content::NotificationRegistrar registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(InstantController);
 };
 
 #endif  // CHROME_BROWSER_UI_SEARCH_INSTANT_CONTROLLER_H_