Cleanup themes that fail to install

Themes which fail to install due to aapt or idmap errors
would not be properly cleaned up. This caused subsequent installs
to give a INSTALL_FAILED_UID_CHANGED (-24) error.

This patch also adds install error codes specifically for themes.

Change-Id: Ie03b92ca0a7dec8c4a5e3725b717943d36abb349