The application context for LauncherAppState is supplied by
the application whenever it starts; don't ask for an
instance before that.
Change-Id: I1ca8ea04238a357a682f79250f08813ead7ae532
Multiple processes may be tracked and viewed simultaneously.
Also, some changes to the graph:
* show uss and pss together
* adjust opacity controls
Change-Id: I20eebaa8cc8faf78b46af2a35d71ee538207f02b