The Mac now supports native combo box widgets so it no longer will crash in GetProperty
with a null mWidget field.
Modified nsComboboxControlFrame::HandleEvents. MouseExit from the combox rect now
initiates mouse capture on the drop-down list.
Modified nsCSSFrameConstructor::ConstructSelectFrame to initialize the drop-down list
for frame-based comboboxes as hidden.
Added a nsIListControlFrame::CaptureMouseEvents method.
Implemented nsListControlFrame::CaptureMouseEvents.
git-svn-id: svn://10.0.0.236/trunk@27879 18797224-902f-48f8-a5cc-f745e15eee43
73c719c037