fix map controls for mission and contacts layers on events page

[matthewberryman]

#82 (comment)

cc @LucieGueuning

[matthewberryman]

I’ve been struggling with the same issue on #134 as I need to update the events layer (also a geoJSON layer); the fix seems to be to just replace the data per Leaflet/Leaflet#1416 (comment) - I will have a go at this on both of these issues when I get back home.

[matthewberryman]

Actually this is slightly different to #134; here simply keeping state on whether or not the control's been added (as I had to do in #134, but in #134 I also had to update the layer too) will fix the bug.

[matthewberryman]

Nope, not quite, per comment I just added on #134 the control gets out of sync.

[matthewberryman]

Keeping track of this control issue here.
I'm first trying to remove the layer, to remove the old control, however it's failing with

Uncaught TypeError: Cannot read property 'indexOf' of undefined
    at e.removeLayer (leaflet.groupedlayercontrol.js:69)
    at landing.js:609

due to a bug in leaflet-groupedlayercontrol, ismyrnow/leaflet-groupedlayercontrol#49 , which won't be completely fixed until ismyrnow/leaflet-groupedlayercontrol#46 is merged (the pull request fixes the bug but also introduces a new feature). I will have to separately fork and patch.

[LucieGueuning]

No auto sync when creating an event. Still need to refresh to see our event on homepage.

[LucieGueuning]

Mission and RSS feed are not on event as layer ON/OFF