Added attribute showForAllUsers that deprecates showOnLockScreen

The new name is more meaningful to what the attribute actually does.

Also, force the FLAG_SHOWN_WHEN_LOCKED flag for windows that belong
to acitivties with the showForAllUsers attribute set.

Bug: 20227306
Change-Id: Ifd49166c3ec0e67ae43addc0fb30038523332ea5
13 files changed