Set map default center even if waiting for user location

There is an edge case when using "locate" a default view AND
activating easing for transitions: in this case, Leaflet.locate needs
a  "starting view" to compute the easing to the new position (the
user location).

I could have only set the default_view when easing is on, but I
thought it was simpler to just set it anyway…

umap/static/umap/js/umap.js

@@ -688,7 +688,11 @@ L.U.Map.include({
       // FIXME An invalid hash will cause the load to fail
       this._hash.update()
     } else if (this.options.defaultView === 'locate' && !this.options.noControl) {
-      this.once('locationerror', this._setDefaultCenter)
+      // When using locate as default map view AND activating easing
+      // Leaflet.locate will ask the map view to compute transition to user
+      // position, so in this case we do need a default center, so let's
+      // set it anyway
+      this._setDefaultCenter()
       this._controls.locate.start()
     } else if (this.options.defaultView === 'data') {
       this.onceDataLoaded(() => {