Update addScopes

Author: kurkle

src/helpers/helpers.config.js

@@ -220,18 +220,22 @@ function resolveFallback(fallback, prop, value) {
   return isFunction(fallback) ? fallback(prop, value) : fallback;
 }
 
+const getScope = (key, parent) => key === true ? parent : resolveObjectKey(parent, key);
+
 function addScopes(set, parentScopes, key, parentFallback) {
   for (const parent of parentScopes) {
-    const scope = key === true ? parent : resolveObjectKey(parent, key);
+    const scope = getScope(key, parent);
     if (scope) {
       set.add(scope);
       const fallback = scope._fallback;
       if (defined(fallback) && fallback !== key && fallback !== parentFallback) {
+        // When we reach the descriptor that defines a new _fallback, return that.
+        // The fallback will resume to that new scope.
         return fallback;
       }
-    } else if (scope === false && (key === 'interaction' || key === 'animation')) {
-      // anything that falls to `interaction` or `animation`, with value `false`,
-      // results to `false`.
+    } else if (scope === false && key !== 'fill') {
+      // Fallback to `false` results to `false`, expect for `fill`.
+      // The special case (fill) should be handled through descriptors.
       return null;
     }
   }