Don't create idmap if app doesn't have resources.arsc

Some apps do not have a restable but some legacy themes
try to theme these apps anyways. In this case we skip
the idmap creation process.

Change-Id: I8bc60984299791733d4fe8c9bbcaa75eca6d736b
Merge "Don't create idmap if app doesn't have resources.arsc" into cm-11.0