grab: Expect motion events before touch-emulated button presses

The current server code for event is clear in that emulated motion
events are expected before emulated button events. Update tests to
match.

Note that in the case of pointer grabs, the first motion event is not
reported because by that time the press event has not happened yet and
the pointer grab is not yet active.
3 jobs for grab-expect-motion-events-before-emulated-presses in 1 minute and 42 seconds (queued for 1 second)
Status Job ID Name Coverage
  Prep
passed #6482683
container-prep

00:00:11

 
  Install Xserver
passed #6482684
xserver-build

00:01:05

 
  Build
passed #6482685
build

00:00:24