Allow passing the permission group name to PermissionUsageFragment.

PermissionUsageFragment can now take in the name of the permission
group instead of the name of the permission.  If both are passed, it
aborts if they are inconsistent.

Also fix a bug with restoring the saved permission filter.

Test: Open Permissions Hub with permission or group name.
Test: Verify Permissions Hub aborts with inconsistent permission and
group names.

Change-Id: I2d6cf802ecc8ba157a725976086866828c386a51