FreeImage: patch 48-bit RGB images with a tRNS chunk
pdComboBox: many rendering fixes
Resize UC: convert combo boxes to pdComboBox
pdScrollBar: fix minor positioning issues
pdTextBox: mirror recent changes to pdComboBox
Unit conversions: harden against DBZ errors
Text up/down UC: switch to pdTextBox

API scrollbars still present an issue here, but it's on my to-do list!
Resize UC: alignment fixes for new text/updown layout
Smart Resize UC: add optional "disable percent mode" property

For the forthcoming New Image dialog, percent is not a valid way to
describe the new image's size.  I still want to use the resize control,
as it covers resolution, inches, cm, etc, but I needed a way to prevent
Percent from being exposed as a measurement option.
New Image dialog: placeholder commit

...so I can sync a bunch of other pending commits.