Fix for NSSplitView's non integral drawing/frame calculations

gistfile1.m

// In an NSSplitView subclass

- (void)drawDividerInRect:(NSRect)rect
{
    [super drawDividerInRect:NSIntegralRect(rect)];
}

// In NSSplitViewDelegate implementation

- (CGFloat)splitView:(NSSplitView *)splitView constrainSplitPosition:(CGFloat)proposedPosition ofSubviewAt:(NSInteger)dividerIndex
{
  return floorf(proposedPosition);
}