Convert track-webvtt-tc[022, 023] tests to testharness.js

third_party/WebKit/LayoutTests/media/track/track-helpers.js

Index: third_party/WebKit/LayoutTests/media/track/track-helpers.js
diff --git a/third_party/WebKit/LayoutTests/media/track/track-helpers.js b/third_party/WebKit/LayoutTests/media/track/track-helpers.js
index c8ee628dedb02ab781a0773ca65aaba140a590a1..a377ae0628c054457dfd5bb0b4ea884d6ced089a 100644
--- a/third_party/WebKit/LayoutTests/media/track/track-helpers.js
+++ b/third_party/WebKit/LayoutTests/media/track/track-helpers.js
@@ -38,4 +38,28 @@ function check_cues_from_track(src, func) {
             func(trackElement.track);
         });
     }, "Check cues from " + src);
+}
+
+function assert_cue_fragment(cue, children) {
+    var fragment = createFragment(children);
+    assert_true(fragment.isEqualNode(cue.getCueAsHTML()));
+}
+
+function createFragment(children) {
+    var fragment = document.createDocumentFragment();
+    cloneChildrenToFragment(fragment, children);
+    return fragment;
+}
+
+function cloneChildrenToFragment(root, children) {
+    for (var child of children) {
+        var childElement;
+        if (child.type == "text") {
+            childElement = document.createTextNode(child.value);
+        } else {
+            childElement = document.createElement(child.type);
+            cloneChildrenToFragment(childElement, child.value);
+        }
+        root.appendChild(childElement);
+    }
 }