Initial stab at a guided walkthrough of enabling accessibility
DEBUG checks on calls to setNeedsLayout:, setNeedsDisplay:, and setNeedsDisplayInRect:

Adapted from @steipete's gist providing the same protections for UIKit.
GET OFF THE MAIN THREAD and maintain higher priority for window list updates than thumbnail updates.
Don't break into debugger on this check anymore.
Merge branch 'numist/performance' into develop
Merge branch 'develop' into numist/accessibility-api-prompt
Some kind of progress
Disabled window controller FC
Create core window controller in app delegate.
Post API Disabled event at core invocation.
BUGFIX: Recreate event tap when state of AX API changes.

Sometimes, when the AX API state changes (notably: when it's enabled by
AppleScript?), the event tap stops receiving key down/up events.
Wharrgarbl.
Activate Switch when presenting the AXDisabled alert window.
Event tap is robust against AX API changes again.
CF properties confuse the static analyzer, use ivars instead.

Bummer.
Decruftify