Use local pages for webrtc telemetry tests.

tools/perf/page_sets/webrtc_cases/canvas-capture.js

+/*
+ * Copyright 2017 The Chromium Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+'use strict';
+
+const DEFAULT_FRAME_RATE = 30;
+
+var canvas = document.getElementById('canvas');
+var context = canvas.getContext('2d');
+
+var remoteVideo = document.getElementById('remoteVideo');
+var startButton = document.getElementById('startButton');
+startButton.onclick = start;
+
+var pc1;
+var pc2;
+var stream;
+
+function logError(err) {
+  console.error(err);
+}
+
+// This function draws a red rectangle on the canvas using
+// requestAnimationFrame().
+function draw() {
+  window.requestAnimationFrame(draw);
+  context.rect(0, 0, canvas.clientWidth, canvas.clientHeight);
+  var randomNumber = Math.random();
+  var hue;
+  if (randomNumber < 0.33)
+    hue = 'red';
+  else if (randomNumber < 0.66)
+    hue = 'green';
+  else
+    hue = 'blue';
+  context.fillStyle = hue;
+  context.fill();
+}
+
+function start() {
+  startButton.onclick = hangup;
+  startButton.className = 'red';
+  startButton.innerHTML = 'Stop test';
+  draw();
+  stream = canvas.captureStream(DEFAULT_FRAME_RATE);
+  call();
+}
+
+function call() {
+  var servers = null;
+  pc1 = new RTCPeerConnection(servers);
+  pc1.onicecandidate = (event) => {
+    if (event.candidate) {
+      pc2.addIceCandidate(event.candidate);
+    }
+  };
+
+  pc2 = new RTCPeerConnection(servers);
+  pc2.onicecandidate = (event) => {
+    if (event.candidate) {
+      pc1.addIceCandidate(event.candidate);
+    }
+  };
+  pc2.onaddstream = (event) => {
+    remoteVideo.srcObject = event.stream;
+  };
+
+  pc1.addStream(stream);
+  pc1.createOffer({
+    offerToReceiveAudio: 1,
+    offerToReceiveVideo: 1
+  }).then(onCreateOfferSuccess, logError);
+}
+
+function onCreateOfferSuccess(desc) {
+  pc1.setLocalDescription(desc);
+  pc2.setRemoteDescription(desc);
+  pc2.createAnswer().then(onCreateAnswerSuccess, logError);
+}
+
+function onCreateAnswerSuccess(desc) {
+  pc2.setLocalDescription(desc);
+  pc1.setRemoteDescription(desc);
+}
+
+function hangup() {
+  pc1.close();
+  pc2.close();
+  pc1 = null;
+  pc2 = null;
+  startButton.onclick = start;
+  startButton.className = 'green';
+  startButton.innerHTML = 'Start test';
+}