fixed: outlineview dropHighlightViewOnRow height was off by 2 pixels

AppKit/CPOutlineView.j

@@ -2006,6 +2006,17 @@ var CPOutlineViewCoalesceSelectionNotificationStateOff  = 0,
     return rect;
 }
 
+/*!
+    @ignore
+*/
+- (CGRect)_rectForDropHighlightViewOnRow:(CPInteger)theRowIndex
+{
+    var rect = [super _rectForDropHighlightViewOnRow:theRowIndex];
+    rect.size.height += 2.0;
+
+    return rect;
+}
+
 /*!
     @ignore
     We need to move the disclosure control too.