Loading a modified route does not show modified shape line without changing zoom level

[flibbertigibbet]

After loading a previously created scenario or colleague's scenario, new stops display, but not the modified route shape. Zooming in or out, the modified shape line appears; zooming back to the original zoom level, it disappears again. Panning seems to have no effect.

[flibbertigibbet]

This is on the 'Add stops' page; after progressing to the 'Add shape' page, the modified route line appears as expected.

[ddohler]

I saw this earlier and assumed it was a caching issue; if you clear the browser cache and go through the same steps, does it show up?

[flibbertigibbet]

On the initial 'Routes' page, the modified route shape appears only on zoom change, but added stops do not appear.

[flibbertigibbet]

A page refresh with the Chrome developer tab open does seem to sort it out, @ddohler.

[CloudNiner]

I'm not totally sure what to do about this. In order to truly fix it, we think need to wipe the browser and windshaft cache on a layer change.

[flibbertigibbet]

This also seems to be related to the seeming issue with adding stops (#545); I think sometimes interactivity doesn't work until zoom level change.