Make it so that <map-extent>.getMeta looks for name=cs type metas.

Revert change to <map-feature>.getFallBackCS to the extent that it once
again relies on <map-extent>.getMeta (which was updated to work for this
use case).

src/map-extent.js

@@ -375,7 +375,7 @@ export class MapExtent extends HTMLElement {
   }
   getMeta(metaName) {
     let name = metaName.toLowerCase();
-    if (name !== 'extent' && name !== 'zoom') return;
+    if (name !== 'extent' && name !== 'zoom' && name !== 'cs') return;
     return this.parentLayer.src
       ? this.querySelector(`:scope > map-meta[name=${name}]`) ||
           this.parentLayer.shadowRoot.querySelector(

src/map-feature.js

@@ -285,30 +285,22 @@ export class MapFeature extends HTMLElement {
   // native cs: used by FeatureLayer._geometryToLayer(...),
   //            the fallback cs for map-geometry if its cs attribute is not specified
   _getFallbackCS() {
-    let csMeta, cs;
+    let csMeta;
     if (this._parentEl.nodeName === 'MAP-LINK') {
-      // feature attaches to link's shadow
-      csMeta = this._parentEl.shadowRoot.querySelector(
-        'map-meta[name=cs][content]'
-      );
-      let linkCS = this._parentEl._templateVars.values.find(
-        (input) => input.units
-      )?.units;
-      cs = csMeta
-        ? M._metaContentToObject(csMeta.getAttribute('content')).content
-        : linkCS
-        ? linkCS
-        : 'gcrs';
+      // feature attaches to link's shadow root
+      csMeta =
+        this._parentEl.shadowRoot.querySelector('map-meta[name=cs][content]') ||
+        this._parentEl.parentElement.getMeta('cs');
     } else {
       let layerEl = this.getLayerEl();
       csMeta = layerEl.src
-        ? layerEl.shadowRoot.querySelector('map-meta[name=cs]')
-        : layerEl.querySelector('map-meta[name=cs]');
-      cs = csMeta
-        ? M._metaContentToObject(csMeta.getAttribute('content')).content
-        : 'gcrs';
+        ? layerEl.shadowRoot.querySelector('map-meta[name=cs][content]')
+        : layerEl.querySelector('map-meta[name=cs][content]');
     }
-    return cs;
+    // even here we could make an effort to use the tref variables to determine
+    // the coordinate system of the response - would only work with WMS, I think
+    // the fallback 'gcrs' SHOULD be specified by the MapML spec 
+    return csMeta ? M._metaContentToObject(csMeta.getAttribute('content')).content : 'gcrs';
   }
 
   // Util functions: