Import wpt@357b83b809e3cbc7a1805e7c3ca108a7980d782f

third_party/WebKit/LayoutTests/imported/wpt/web-animations/testcommon.js

Index: third_party/WebKit/LayoutTests/imported/wpt/web-animations/testcommon.js
diff --git a/third_party/WebKit/LayoutTests/imported/wpt/web-animations/testcommon.js b/third_party/WebKit/LayoutTests/imported/wpt/web-animations/testcommon.js
index e375a0f8741788984f9c7be658a3b88c7396c0ff..31ebdfaf279deca00ef5384fd7d347e1cf00e8e1 100644
--- a/third_party/WebKit/LayoutTests/imported/wpt/web-animations/testcommon.js
+++ b/third_party/WebKit/LayoutTests/imported/wpt/web-animations/testcommon.js
@@ -158,3 +158,19 @@ function waitForAnimationFrames(frameCount) {
     window.requestAnimationFrame(handleFrame);
   });
 }
+
+// Continually calls requestAnimationFrame until |minDelay| has elapsed
+// as recorded using document.timeline.currentTime (i.e. frame time not
+// wall-clock time).
+function waitForAnimationFramesWithDelay(minDelay) {
+  var startTime = document.timeline.currentTime;
+  return new Promise(function(resolve) {
+    (function handleFrame() {
+      if (document.timeline.currentTime - startTime >= minDelay) {
+        resolve();
+      } else {
+        window.requestAnimationFrame(handleFrame);
+      }
+    }());
+  });
+}