Fix #155437855: "dumpsys activity" package filtering doesn't filter everything

Clean up various code paths to correctly use the "packageName" option to
limit its output to only information about that package.

Also do a little re-arranging of the output to cleanup a bit recent
stuff that was added, so the end of the output is still the important
high-level summary of process states.

Bug: 155437855
Test: manually inspected various "dumpsys activity" output.
Change-Id: I2ebe6f7ab3d433281993eb3959d375e2e53e0df9