L.TileLayer.bringToFront()/Back() broken in IE8

[tnightingale]

These functions result in a call to getElementsByClassName() (https://github.com/CloudMade/Leaflet/blob/master/src/layer/tile/TileLayer.js#L169) which isn't supported by <IE8.
Maybe querySelectorAll() can be used instead?

I'm not sure what Leaflet's policy is on supporting oldIE these days.

[mourner]

Oops, should have missed that, Leaflet supports IE6+

[snkashis]

@mourner, would a polyfill in DomUtil be appropriate to fix this up?