Modern keyboard: suppress 'Microsoft Candidate uI' message and handle touch keyboard's name change event. Re #7273.
In Version 1803 (April 2018 Update), 'Microsoft Candidate UI' is announced whenever candidates appear. As this is anoying, suppress this.
Also, reported by a user: under some circumstances, touch keyboard keys fire name change event, which results in NVDA announcing characters. Thus suppress this as well.