Fix bug 1009583 - Font size menu is now variable width
Fix bug 1009583 - Font size menu is now variable width

This patch makes the font size selection menu variable width,
by removing the explict CSS width declaration.

humphd/thimble.mozilla.org,mozilla/thimble.mozilla.org,mozilla/thimble.mozilla.org,humphd/thimble.mozilla.org,humphd/thimble.mozilla.org,mozilla/thimble.mozilla.org,mozilla/thimble.mozilla.org,humphd/thimble.mozilla.org