UITest/writer_tests: FAIL: test_tracked_changes_reject (trackedChanges.trackedchanges)

observed the following failure in today's master build:

======================================================================
FAIL: test_tracked_changes_reject (trackedChanges.trackedchanges)
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Traceback (most recent call last):
  File "master/sw/qa/uitest/writer_tests/trackedChanges.py", line 98, 
in test_tracked_changes_reject
    self.assertEqual(document.Text.String[0:1], "")
AssertionError: 'T' != ''
- T
+


my pet theory based entirely on speculation is that in the test code:

        self.xUITest.executeCommand(".uno:TrackChanges")
        type_text(xWriterEdit, "Test LibreOffice")
        self.xUITest.executeCommand(".uno:ShowTrackedChanges")

the ".uno:TrackChanges" is somehow async dispatched and there is a loop 
(in WindowUIObject::execute) to convert the "TYPE" action into a 
KeyEvent per character and somehow after handling of the first "T" the 
async event of the ".uno:TrackChanges" is executed.

does the UITest use processEventsToIdle at some point to avoid reorderings?