Add test for sending square resolution video on a PeerConnection.

content/test/data/media/webrtc_test_utilities.js

Index: content/test/data/media/webrtc_test_utilities.js
diff --git a/content/test/data/media/webrtc_test_utilities.js b/content/test/data/media/webrtc_test_utilities.js
index c56953fd2cbe64edf2e66019527d09dfc4183432..644a812565ee821798a7120819cff6aeba41d5d8 100644
--- a/content/test/data/media/webrtc_test_utilities.js
+++ b/content/test/data/media/webrtc_test_utilities.js
@@ -72,12 +72,22 @@ function detectVideo(videoElementName, predicate, callback) {
         predicate(pixels, oldPixels)) {
       console.log('Done looking at video in element ' + videoElementName);
       clearInterval(waitVideo);
-      callback();
+      callback(videoElement.videoWidth, videoElement.videoHeight);
     }
     oldPixels = pixels;
   }, 200);
 }
 
+function waitForVideoWithResolution(element, expected_width, expected_height) {
+  addExpectedEvent();
+  detectVideoPlaying(element,
+      function (width, height) {
+        assertEquals(expected_width, width);
+        assertEquals(expected_height, height);
+        eventOccured();
+      });
+}
+
 function waitForVideo(videoElement) {
   addExpectedEvent();
   detectVideoPlaying(videoElement, function () { eventOccured(); });