Explicitly remove the completeEdit onblur event listener

When the completeEdit is invoked by keystroke, we don't want it invoked
a second time as a result of its own action removing the input field.

Firefox does *not* call the "blur" event when a focused input element is removed.
Chromium *does* call the "blur" event when a focused input element is removed.

So this is needed for Chromium.