Possible fix for [http://core.tcl.tk/tcl/info/4955f5d8a4dce006e063f924bc9709f7850ecb6a|4955f5d8a4]
Make the "scrollbar" a real Tcl_Obj-based command. No change in functionality.
Some more places where Tcl_Obj's can be used
Make "scrollbar" a Tcl_Obj-based command
Some more Tcl_Obj-related optimizations
remove TODO: scrollbars use Tcl_Obj API now