restore store's contract-404 handling for custom billing, keeping the page's own error texts

Author: tobihagemann

assets/js/hubsubscription.js

@@ -269,12 +269,15 @@ class HubSubscription {
       this.onLoadCustomBillingSucceeded(data);
       continueHandler();
     }).fail(xhr => {
-      this.onLoadCustomBillingFailed('Loading custom billing options failed.');
+      this.onLoadCustomBillingFailed(xhr.status, 'Loading custom billing options failed.');
+      // store's documented answer for "this hub has no custom billing" is a 404 with a JSON error body
+      if (xhr.status == 404 && xhr.responseJSON?.status == 'error') {
+        continueHandler();
+      }
     });
   }
 
   onLoadCustomBillingSucceeded(data) {
-    // custom_billing is null when the hub has no custom billing
     this._subscriptionData.customBilling = data.custom_billing || null;
     if (this._subscriptionData.customBilling) {
       this._subscriptionData.quantity = this._subscriptionData.customBilling.quantity || this._subscriptionData.quantity;
@@ -284,8 +287,13 @@ class HubSubscription {
     this._subscriptionData.inProgress = false;
   }
 
-  onLoadCustomBillingFailed(error) {
-    this._subscriptionData.errorMessage = error;
+  onLoadCustomBillingFailed(status, error) {
+    if (status == 404) {
+      this._subscriptionData.customBilling = null;
+      this._subscriptionData.errorMessage = '';
+    } else {
+      this._subscriptionData.errorMessage = error;
+    }
     this._subscriptionData.inProgress = false;
   }