Adjust instruction sets for shared UID apps.

Since shared UID apps are run in the same process,
we'll need to make sure they're compiled for the same
instruction set.

This change implements the recompilation of apps that
don't have any ABI constraints.

Apps that *do* have ABI constraints are harder to deal
with, since we'll need to rescan them to figure out the
full list of ABIs they support and then re-extract the
native libraries from these apps once we find an ABI we
can use throughout.

Change-Id: I365c6b0b18187df814d4736da61b199dd4494e3c