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

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

Change-Id: If22e8b245f688d922c168aa54c8acf743c0644d7
GC triggering performance optimizations

Credits to team CM.

Change-Id: Id491a095f2faaf1e05fb44525063254bcff0a2bc