Fix issue #8311263: Corrupted UI across all tabs in People app

The problem is that there are other configurations that the
action bar can be in that ActionBarOverlayLayout didn't account
for -- such as here, the nav part visible but the rest hidden.

Fixing this was non-trivial because it means that to correctly
implement fitSystemWindows() we need to in these cases take the
actual measured height of the action bar for positioning the
content view...  but that is not yet available, since
fitSystemWindows() must run before layout.

To solve this, ActionBarOverlayLayout now inherits directly from
ViewGroup and implements its own custom layout.  In its measure
pass it does all of the fitSystemWindows() work that is dependent
on the measured sizes of the action bar child views after those
are measured and applies them to the content view before it is
measured.

Change-Id: Ie327075d502e9c348aa80b0968c6b0403478301e