Converted comctl_windows.go to use the new string wrapper functions.
Converted comctl_windows.go to use the new string wrapper functions.

robbiev/ui,hajimehoshi/ui,292388900/ui,robbiev/ui,HunterChen/ui,hajimehoshi/ui,UIKit0/ui,ProtonMail/ui,janstk/ui,UIKit0/ui,ProtonMail/ui,beni55/ui,robbiev/ui,beni55/ui,ProtonMail/ui,hajimehoshi/ui,HunterChen/ui,beni55/ui,cainiaocome/ui,cainiaocome/ui,janstk/ui,UIKit0/ui,292388900/ui,292388900/ui,janstk/ui,cainiaocome/ui,mirrr/ui,mirrr/ui,HunterChen/ui,mirrr/ui