Add GM_apiLeakCheck() calls to _deleteValue and _listValues.
Add GM_apiLeakCheck() calls to _deleteValue and _listValues.

Signed-off-by: Johan Sundström <ca208e76908adac3e13b149d26b4af116cbba60c@gmail.com>
HasClass0/greasemonkey,the8472/greasemonkey,HasClass0/greasemonkey,Martii/greasemonkey,Ventero/greasemonkey,the8472/greasemonkey,Martii/greasemonkey,Ventero/greasemonkey