Treat default value that wasn't found as empty value.

Fixes http://code.google.com/p/android/issues/detail?id=33220

Change-Id: If22e8b245f688d922c168aa54c8acf743c0644d7
Add clear all recents action to recents panel

Change-Id: I2243ebc83abc483e78b112900a653d7e61edc5ba