Bug 1430173 - Add Timer Rounding tests backported from -central to -esr. r=baku, a=RyanVM

MozReview-Commit-ID: Jl4WZAamgrI

--HG--
extra : transplant_source : E%DC%91lU%1C%A4l%2C%C8%23PCz%EB%F2%81%25%1F%90

1 files changed, 28 insertions, 0 deletions

diff --git a/dom/tests/mochitest/general/worker_child.js b/dom/tests/mochitest/general/worker_child.js
new file mode 100755
index 000000000..fa340fc65
--- /dev/null
+++ b/dom/tests/mochitest/general/worker_child.js
@@ -0,0 +1,28 @@
+let timeStampCodes;
+let worker = new Worker("worker_grandchild.js");
+
+function listenToParent(event) {
+  self.removeEventListener("message", listenToParent);
+  timeStampCodes = event.data;
+
+  let timeStamps = [];
+  for (let timeStampCode of timeStampCodes) {
+    timeStamps.push(eval(timeStampCode));
+  }
+  // Send the timeStamps to the parent.
+  postMessage(timeStamps);
+
+  // Tell the grandchild to start.
+  worker.postMessage(timeStampCodes);
+}
+
+// The worker grandchild will send results back.
+function listenToChild(event) {
+  worker.removeEventListener("message", listenToChild);
+  // Pass the results to the parent.
+  postMessage(event.data);
+  worker.terminate();
+}
+
+worker.addEventListener("message", listenToChild);
+self.addEventListener("message", listenToParent);