Use boolean literals for bool property defaults

This makes property initializer lists in interpreter constructors a
little nicer to read.

BUG=none
TEST=cros_workon_make --test chromeos-base/gestures

Change-Id: I5a596aad6aa703b45de1809510c0de1950d82790
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/gestures/+/3985918
Reviewed-by: Sean O'Brien <seobrien@chromium.org>
Commit-Queue: Harry Cutts <hcutts@chromium.org>
Tested-by: Harry Cutts <hcutts@chromium.org>