Fix flaky test AccessibilityWindowQueryTest#testWindowDockAndUndock_dividerWindowAppearsAndDisappears

It's a flaky test.
Check the divider window if it is presented by a11y events,
TYPE_WINDOW_CONTENT_CHANGED, TYPE_WINDOWS_CHANGE.
And verify and pass the test case for 10 times.

Bug: 149725344
Test: atest android.accessibilityservice.cts.AccessibilityWindowQueryTest#testWindowDockAndUndock_dividerWindowAppearsAndDisappears --iteration
Change-Id: I10534bf98d90295250f8e075c97501287067cc50
1 file changed