container param in DomEvent.getMousePosition not optional anymore

[nrenner]

Since PR #1826 the container param is not optional anymore (Line 141). This is breaking the v0.6 Leaflet.zoomslider plugin with an undefined error on slider click.

As it is also an API change, this is probably a Leaflet regression?

[mourner]

Yep, you're right, I missed that! @scooterw thoughts?

[scooterw]

I obviously did not think about that case. Apologies to @nrenner and anyone else this has bitten. I will take a better look at this tonight and try to get a fix in place.