How can "forceConsider" be set to true?

I need to set forceConsider argument to _onKeyDown function in event_handler.js to true. How can this be done?

The reason I need that is that I need to be able to cancel an action with an escape key, regardless of where the target is. In my case, the target sometimes falls into the black list of _shouldConsider function, and then my code doesn't work.

Thanks a lot.