Fix small cosmetic issues with the reroute node: 1. Remove special case that allowed curved links to attach vertically. 2. Center align the reroute node's label. The vertically attached node links could lead to kinks in the otherwise smooth curves. This would break the visual flow and make the link potentially intersect the node's label. The center alignment of the label gives more consistent results for different label lengths and also reduces the chance of the label interfering with the node links. Reviewed By: Hans Goudey, Pablo Vazquez Differential Revision: D14457