Only use foreground process info if valid

getProcessInfo() returned _foregroundProcessInfo without checking the
return value of updateForegroundProcessInfo() indicating whether
_foregroundProcessInfo was non-existent or invalid.

I think this might be the solution to a bunch of recent crash bugs,
but not closing them as I can't test.

Also skipping RB because it is a simple patch and RB is down from here.

CCBUG: 372401
CCBUG: 372620
CCBUG: 372619
CCBUG: 372593
(cherry picked from commit 40b1f0e8)