nvda

b4579327 - Report live region changes outside of web content (E.g. settings search messages, Windows update progress on logon, and Skype for business chat messages etc) (#7287)

Report live region changes outside of web content (E.g. settings search messages, Windows update progress on logon, and Skype for business chat messages etc) (#7287) * A very simple implementation for ARIA live regions outside of web content. UIA's liveRegionChanged event, and MSAA's object_liveRegionChanged event are mapped to a new liveRegionChange event in NVDA. the base NVDAObject handles this event by simply reporting the name of the object in speech and braille. * MSHTML NVDAObject: stub out event_liveRegionChange as MSHTML already has custom live region support via virtualBuffers that is much more accurate. * Automatically report incoming messages in Skype for Business while in a chat window. * Add the EVENT_OBJECT_LIVEREGIONCHANGED MSAA constant to winUser. * For now, do not allow UI Automation live region events with the same text within a short time of each other. Multiple apps in windows 10 (Maps, Store etc) have buggy events. No runtimeID check can be made here as in many cases multiple elements in a list (E.g. store updates for each app) are firing all at the same time. * Added a _shouldAllowUIALiveRegionChangeEvent property to UIA NVDAObject. This is private as it may be changed or removed in the future when live region events are rethought in Windows 10. this property compairs the text and time against the last liveRegion change.