Backout change for dismissing hint list

This is for #6392 .

@YuAo This backs out part of your fix for https://github.com/adobe/brackets/pull/6242 because it introduces issue #6392 which is worse. I tried to find a way to fix both, but haven't been able to find anything reasonable, so I want to make this change for now. You're welcome to take another look at this.