It's simpler to check the safety net directly inside the
function that checks for auto-correction threshold.

This introduces one very slight change in behavior. The value
checked by the safety net is not any more the "typed word" but the
"considered word", the difference being any possibly appended
single quotes.
E.g. the user types "this'''" : the typed word is "this'''" but
the considered word is "this".
This change in behavior can be considered a bugfix.

Change-Id: Ia7ab4bc933183dfbd41bb00328e4c0b5ab76bc63