Themes: Fix setting wallpaper from a legacy theme

Change-Id: I3bfc9ee24d2a3ee5c1bdb97f2c07427e6d723206
Themes: Track NotFoundException on app launch failure

We should probably keep an eye on NotFoundExceptions too since they
are a common exception thrown when a bad theme is applied.

Change-Id: I2ccaed0349a90ab99b99fb83cef0c9183d598088
Themes: Remove listener if exception is thrown

If something goes wrong and a client does not remove itself, the
theme manager may still have a reference to the listener and an
exception is thrown while trying to call one of the listener's methods.
When this happens, we should not only log it but remove the bad listener.

Change-Id: I052cdcc10b0eaa75ebf076b3ece5f8a668d3868e