This test checks the keypress repeat speed. However, there is inevitable
delay incurred by each keypress and thus we cannot be 100% certain about
the number of keypress to expect. Let's set a range instead of expecting
a fixed amount of keypress.
BUG=chrome-os-partner:10287
TEST=Test passed
Change-Id: Ib43bead68e5497cd64251fb45fab522cbaf3ea86
Reviewed-on: https://gerrit.chromium.org/gerrit/26533
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Commit-Ready: Vic Yang <victoryang@chromium.org>
Tested-by: Vic Yang <victoryang@chromium.org>