Blender Git Loki

Fix #29958: Search Menu keeps hiding first character(s) after long input

- ui_check_but() in ui_textedit_move() is necessary because this function clips
but->drawstring to fit text entry widget and it confuses cursor movement stuff.
ui_check_but copies editstring to drawstring, so displaystring would be clipped
again in correct way.
- If the whole drawstring fits widget, no need to set button's offset.