improve accessibility of the editor by output more infos over UIA

[christopherpross]

Hey Guys,
I don't know whether I am here on the right place, but I will try this.
The Editor component of VS has some accessibility problems, because some infos are not communicated over the UIA interface or are wrong.

• The Linenumbers are always characters as TextUnit, that is nice, but if you enable "show line numbers" in Visual studio, this numbers will always take in the selectedTextRange in the UIA-Framework, if you go on the begin of a line.
• the Tags like ErrorTag and other classifiers are not exposed to the UIA interface, so no screenreader can get infos about that.
• Something seems wrong with the TextRange and Move, if you enable the Line numbers, the indexes are not right or the textrange gives strange values back.

The Issues could be resolved with a custom UIA pattern and some fixes, let's try to find a solution for this problems because this would give the accessibility of the whole VS a very push forward.

all the best,
Christopher

[gundermanc]

+@DanteGagne our accessibility expert