Followup: overwrite mode remaining issues

[redmunds]

These are some loose ends for the new overwrite mode feature

• Larz: If it's not too difficult to implement, don't show background color animation when status bar indicator is clicked
• Track CodeMirror scrollCursorIntoView() issue: scrollCursorIntoView() doesn't always show entire character following cursor codemirror/codemirror5#2254. UPDATE: this is fixed in CodeMirror v4 branch and Brackets cmv4 branch.
• Mac: keyboard shortcut - there may be an existing one, but none of the suggestions I found online worked. Otherwise, a keyboard shortcut should be defined. Maybe contol-i
• Add unit tests

cc @WebsiteDeveloper

[lkcampbell]

@redmunds, one of the suggestions for a specific Mac shortcut (number 2) is using the control key. The control key is hardly ever used on the Mac. The only ctrl-alpha combo I see being used in the code core is ^L for select line. Every other letter is available. Could be ^i, could be ^o.

[redmunds]

If there is not an existing Mac keyboard shortcut, then I vote for control-i (not Cmd-i).

[redmunds]

I researched unit tests for this. Brackets does not have any unit tests document editing via keyboard events -- these belong in CodeMirror.

Also, it would be easy to add a shortcut for Mac, but nobody has asked for one, so I'm not going to take up a shortcut for an unused feature.

Closing.