Clarify docstrings for center param in Map to show coordinate order…

…ing in LngLat. (#5042)

docs/_posts/examples/3400-01-01-simple-map.html

@@ -11,8 +11,8 @@
 <script>
 var map = new mapboxgl.Map({
     container: 'map', // container id
-    style: 'mapbox://styles/mapbox/streets-v9', //stylesheet location
-    center: [-74.50, 40], // starting position
+    style: 'mapbox://styles/mapbox/streets-v9', // stylesheet location
+    center: [-74.50, 40], // starting position [lng, lat]
     zoom: 9 // starting zoom
 });
 </script>

src/ui/map.js

@@ -186,7 +186,7 @@ const defaultOptions = {
  * @param {boolean} [options.doubleClickZoom=true] If `true`, the "double click to zoom" interaction is enabled (see {@link DoubleClickZoomHandler}).
  * @param {boolean|Object} [options.touchZoomRotate=true] If `true`, the "pinch to rotate and zoom" interaction is enabled. An `Object` value is passed as options to {@link TouchZoomRotateHandler#enable}.
  * @param {boolean} [options.trackResize=true]  If `true`, the map will automatically resize when the browser window resizes.
- * @param {LngLatLike} [options.center=[0, 0]] The inital geographical centerpoint of the map. If `center` is not specified in the constructor options, Mapbox GL JS will look for it in the map's style object. If it is not specified in the style, either, it will default to `[0, 0]`.
+ * @param {LngLatLike} [options.center=[0, 0]] The inital geographical centerpoint of the map. If `center` is not specified in the constructor options, Mapbox GL JS will look for it in the map's style object. If it is not specified in the style, either, it will default to `[0, 0]` Note: Mapbox GL uses longitude, latitude coordinate order (as opposed to latitude, longitude) to match GeoJSON.
  * @param {number} [options.zoom=0] The initial zoom level of the map. If `zoom` is not specified in the constructor options, Mapbox GL JS will look for it in the map's style object. If it is not specified in the style, either, it will default to `0`.
  * @param {number} [options.bearing=0] The initial bearing (rotation) of the map, measured in degrees counter-clockwise from north. If `bearing` is not specified in the constructor options, Mapbox GL JS will look for it in the map's style object. If it is not specified in the style, either, it will default to `0`.
  * @param {number} [options.pitch=0] The initial pitch (tilt) of the map, measured in degrees away from the plane of the screen (0-60). If `pitch` is not specified in the constructor options, Mapbox GL JS will look for it in the map's style object. If it is not specified in the style, either, it will default to `0`.