[File Manager] Keep showing GDrive promo banner while the search box is being used.

chrome/browser/resources/file_manager/js/file_manager.js

 // Copyright (c) 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.
 
 /**
  * FileManager constructor.
  *
  * FileManager objects encapsulate the functionality of the file selector
  * dialogs, as well as the full screen file manager application (though the
  * latter is not yet implemented).
@@ skipping 4334 matching lines @@
         localStorage[WELCOME_HEADER_COUNTER_KEY] = ++counter;
         showBanner('header', 'GDATA_WELCOME_TEXT_SHORT');
       } else {
         closeBanner();
       }
     }
 
     function closeBanner() {
       self.directoryModel_.removeEventListener('scan-completed',
           maybeShowBanner);
-      self.directoryModel_.removeEventListener('rescan-completed',
-          maybeShowBanner);
 
       self.dialogContainer_.removeAttribute('gdrive-welcome');
       // Stop showing the welcome banner.
       localStorage[WELCOME_HEADER_COUNTER_KEY] = WELCOME_HEADER_COUNTER_LIMIT;
     }
 
     this.directoryModel_.addEventListener('scan-completed', maybeShowBanner);
-    this.directoryModel_.addEventListener('rescan-completed', maybeShowBanner);
 
     var style = this.document_.createElement('link');
     style.rel = 'stylesheet';
     style.href = 'css/gdrive_welcome.css';
     this.document_.head.appendChild(style);
   };
 })();