Fix gesture exclusion limit for sticky-hide nav bar

If a window hides navigation bar by using WindowInsetsController with
BEHAVIOR_SHOW_TRANSIENT_BARS_BY_SWIPE, there should not be limit about
system gesture exclusion.

Fix: 167782678
Test: SystemGestureExclusionRectsTest
Change-Id: I1573e9ee1976108b41d2cfa827dc599fcae3b6d1