Bug 1696452: Handle attempts to construct JS-implemented interfaces in non-Window globals. r=peterv

We don't want to support this, but we also shouldn't crash if someone attempts
it.

Differential Revision: https://phabricator.services.mozilla.com/D108093

dom/bindings/BindingUtils.cpp

@@ -2559,6 +2559,10 @@ void ConstructJSImplementation(const char* aContractId,
     AutoNoJSAPI nojsapi;
 
     nsCOMPtr<nsPIDOMWindowInner> window = do_QueryInterface(aGlobal);
+    if (!window) {
+      aRv.ThrowInvalidStateError("Global is not a Window");
+      return;
+    }
     if (!window->IsCurrentInnerWindow()) {
       aRv.ThrowInvalidStateError("Window no longer active");
       return;