1 files changed, 31 insertions, 0 deletions
diff --git a/testing/web-platform/tests/resources/test-only-api.js b/testing/web-platform/tests/resources/test-only-api.js
new file mode 100644
index 0000000000..a66eb44ede
--- /dev/null
+++ b/testing/web-platform/tests/resources/test-only-api.js
@@ -0,0 +1,31 @@
+'use strict';
+
+/* Whether the browser is Chromium-based with MojoJS enabled */
+const isChromiumBased = 'MojoInterfaceInterceptor' in self;
+/* Whether the browser is WebKit-based with internal test-only API enabled */
+const isWebKitBased = !isChromiumBased && 'internals' in self;
+
+/**
+ * Loads a script in a window or worker.
+ *
+ * @param {string} path - A script path
+ * @returns {Promise}
+ */
+function loadScript(path) {
+  if (typeof document === 'undefined') {
+    // Workers (importScripts is synchronous and may throw.)
+    importScripts(path);
+    return Promise.resolve();
+  } else {
+    // Window
+    const script = document.createElement('script');
+    script.src = path;
+    script.async = false;
+    const p = new Promise((resolve, reject) => {
+      script.onload = () => { resolve(); };
+      script.onerror = e => { reject(`Error loading ${path}`); };
+    })
+    document.head.appendChild(script);
+    return p;
+  }
+}