added audioplayer contrib module

libraries/wavesurfer/src/util/frame.js

@@ -0,0 +1,13 @@
+import reqAnimationFrame from './request-animation-frame';
+
+/**
+ * Create a function which will be called at the next requestAnimationFrame
+ * cycle
+ *
+ * @param {function} func The function to call
+ *
+ * @return {func} The function wrapped within a requestAnimationFrame
+ */
+export default function frame (func) {
+    return (...args) => reqAnimationFrame(() => func(...args));
+}