This assumes that the metadata is correctly defined in fstab.
Which apparently some devices don't do.
Bug: 8766487
Bug: 12112624
Change-Id: I1b14b9d4c888e9348527984be3dce04bdd9f4de0
When installing a package, we should have /tmp and /cache mounted and
nothing else. Ensure this is true by explicitly mounting them and
unmounting everything else as the first step of every install.
Also fix an error in the progress bar that crops up when you do
multiple package installs in one instance of recovery.
Change-Id: I4837ed707cb419ddd3d9f6188b6355ba1bcfe2b2