Suspend packages - new API for retrieving the suspended status

Instead of always rebuilding the full ApplicationInfo for a
package when callers are only interested in the suspended status
add a new fast API in Packagemanager (which only checks the
suspended user setting for the requested package and returns
a boolean) and change the appropriate caller code too.

Bug: 26794775
Bug: 22776761
Change-Id: Ide8428ef734479360d5a8a75fd8e0ed8ddf2da7a