Log if installers drop attribute installLocation

Installers that don't respect installLocation from APKs may result
in a bad user experience when users use adoptable storage. We still
allow this, but just log it.

Bug: 109668833
Test: Install APKs that explicitly set installLocation, and check
      the installLocation from install session.
Change-Id: Idfb33e79cb0df75af68faa3a70ea8559ea1ca003