Fix mouse wheel scrolling of ComboBox in IE11 (#16918)
IE11 is broken so that the simple implementation always moves up on any
mouse wheel event. Therefore, this change borrows the approach taken by
Escalator for low-level handling of mouse wheel events in a way compatible
with all supported browsers.
Change-Id: I98c89d3ccfeea38d6a454ef708f0eb7d1d3f480c