Per-property transitions are not parsed from style

[1ec5]

16c435b inadvertently removed the call to parseTransitionOptions() and thus support for per-property transitions in style JSON. This would represent a regression from iOS SDK v3.3.x and Android SDK v4.1.0.

Per mapbox/mapbox-gl-js#2788, mapbox/mapbox-gl-style-spec#171, and mapbox/mapbox-gl-test-suite#116, the current plan is to give per-property transitions all the trappings of a formal style specification feature, so here’s one more: the developer might expect to be able to configure per-property transitions using the runtime styling API, now that they can configure style-wide transitions (#7711).

/cc @jfirebaugh @incanus

[1ec5]

the developer might expect to be able to configure per-property transitions using the runtime styling API

#8010 tracks adding runtime styling support for per-attribute transitions to the iOS and macOS SDKs.

[incanus]

Just as a point of clarification, since I was a little fuzzy on this, having e.g. a value for text-color-transition in the original style would cause runtime styling changes to text-color to transition. And then #8010 exposes such transition properties in code.