Fix didn't bypass touch events with non-empty passthrough Region

When the action down motion event contains in the
mTouchExplorationPassthroughRegion, Touchxplorer didn't bypass the
motion event due to enabled multi-finger gesture.

Bug: 152597224
Test: manual test with set mult-finger-gesture enabled non-empty
      passthrough region
      atest CtsAccessibilityServiceTestCases:TouchExplorerTest
      atest FrameworksServicesTests:TouchExplorerTest
Change-Id: Ifef6a4da98aca8144bfd6deaceb1a110cfdbe5df