Run es module test only on browsers with native support

Author: Lars den Bakker

tests/index.html

@@ -23,7 +23,7 @@
 </script>
 <script src="../../web-component-tester/browser.js"></script>
 <script>
-  WCT.loadSuites([
+  const suites = [
     'html/HTMLImportsLoaded-native.html',
     'html/HTMLImports-lazy.html',
     'html/link-import.html',
@@ -50,7 +50,13 @@
     'html/import-for-element.html',
     'html/ready-state.html',
     'html/resolve-path.html',
-    'html/load-imports.html',
-    'html/es-module.html',
-  ]);
+    'html/load-imports.html'
+  ];
+
+  // Only run this test on browsers that supports es modules natively
+  if ('noModule' in document.createElement('script')) {
+    suites.push('html/es-module.html')
+  }
+
+  WCT.loadSuites(suites);
 </script>