Fixed crash in indentation guides when indent size is 0.
Fixed crash in indentation guides when indent size is 0.

R1dO/scintilla_clone,R1dO/scintilla_clone,R1dO/scintilla_clone,R1dO/scintilla_clone,R1dO/scintilla_clone,R1dO/scintilla_clone,R1dO/scintilla_clone,R1dO/scintilla_clone