53457 - multiple items can be selected in select size=1 or in single select listbox
50376 - Cannot select with DOM option on dynamically created SELECT element
62442 - Incorrect extended selection behavior in listboxes
First big change is getting rid of local variables for border and padding and use the ones in the reflow state
Changed "IsInDropDownMode() == PR_TRUE && mComboboxFrame" to "IsInDropDownMode() == PR_TRUE"
Fix for regression from changing of how key events work (no bug assigned), this fix enabled the user to hit 'f' or 'F' and get to the first item that start with 'f' or 'F'
r=kmcclusk sr=buster
git-svn-id: svn://10.0.0.236/trunk@83901 18797224-902f-48f8-a5cc-f745e15eee43