webrtc wpt: add missing pc.close during cleanup

running the html.js/codemod-peerconnection-addcleanup from the tools directory showed some places where a pc.close was missing

BUG=836871

Change-Id: I135db200a4269eccfafc43217b66584603101434
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1610767
Commit-Queue: Philipp Hancke <philipp.hancke@googlemail.com>
Reviewed-by: Henrik Boström <hbos@chromium.org>
Cr-Commit-Position: refs/heads/master@{#661283}

third_party/blink/web_tests/external/wpt/webrtc/RTCCertificate-postMessage.html

@@ -42,9 +42,10 @@
             iframe.contentWindow.postMessage(certificate, "*");
             let certificate2 = await promise;
 
-            new RTCPeerConnection({certificates: [certificate]});
-
-            new RTCPeerConnection({certificates: [certificate2]});
+            const pc1 = new RTCPeerConnection({certificates: [certificate]});
+            t.add_cleanup(() => pc1.close());
+            const pc2 = new RTCPeerConnection({certificates: [certificate2]});
+            t.add_cleanup(() => pc2.close());
 
             assert_equals(certificate.expires, certificate2.expires);
             for (let fingerprint of certificate2.getFingerprints())

third_party/blink/web_tests/external/wpt/webrtc/RTCDataChannel-send.html

@@ -300,6 +300,7 @@
 
 promise_test(async t => {
   let pc1 = new RTCPeerConnection();
+  t.add_cleanup(() => pc1.close());
   let [channel1, channel2] = await createDataChannelPair(pc1);
   let message = 'hello888'; // 8 bytes
   while (message.length <= pc1.sctp.maxMessageSize) {

third_party/blink/web_tests/external/wpt/webrtc/RTCIceTransport-extension.https.html

@@ -98,7 +98,7 @@ promise_test(async t => {
   iceTransport.gather({});
   let candidate;
   do {
-    ({ candidate } = await watcher.wait_for('icecandidate'));
+    (({ candidate } = await watcher.wait_for('icecandidate')));
   } while (candidate !== null);
   assert_equals(iceTransport.gatheringState, 'gathering');
   await watcher.wait_for('gatheringstatechange');

third_party/blink/web_tests/external/wpt/webrtc/RTCPeerConnection-setLocalDescription.html

@@ -125,6 +125,7 @@
 
   promise_test(async t => {
     const pc = new RTCPeerConnection();
+    t.add_cleanup(() => pc.close());
     const offer = await pc.createOffer();
     let eventSequence = '';
     const signalingstatechangeResolver = new Resolver();

third_party/blink/web_tests/external/wpt/webrtc/RTCRtpParameters-transactionId.html

@@ -63,6 +63,7 @@
    */
   promise_test(async t => {
     const pc = new RTCPeerConnection();
+    t.add_cleanup(() => pc.close());
     const { sender } = pc.addTransceiver('audio');
     await doOfferAnswerExchange(t, pc);
 
@@ -73,7 +74,6 @@
     validateSenderRtpParameters(param2);
 
     assert_not_equals(param1.transactionId, param2.transactionId);
-
   }, `sender.getParameters() should return different transaction IDs for each call`);
 
   /*