during the width calculation
* used _TabExpandedStyledWidth() at all places that need to expand tabs,
fixing #4822
* removed _StyledWidthUTF8Safe() as it didn't make sense - we now perform
the same auto-scrolling horizontally as we do vertically
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@33713 a95241bf-73f2-0310-859d-f6bbb57e9c96