MediaRecorder: add and wire read {video,audio}BitsPerSecond props

third_party/WebKit/LayoutTests/fast/mediarecorder/MediaRecorder-creation.html

 <!DOCTYPE html>
 <script src=../../resources/testharness.js></script>
 <script src=../../resources/testharnessreport.js></script>
 <script>
 // This test verifies that MediaRecorder can be created with different Media
 // Stream Track combinations: 1 Video Track only, 1 Audio Track only and finally
 // a Media Stream with both a Video and an Audio Track. Note that recording is
 // _not_ started in this test, see MediaRecorder-basic-video.html for it.
 
 function makeAsyncTest(constraints, verifyStream, message) {
-    return async_test(function(test) {
+    async_test(function(test) {
 
-        var gotStream = test.step_func(function(stream) {
+        const gotStream = test.step_func(function(stream) {
             verifyStream(stream);
 
-            try {
-                recorder = new MediaRecorder(stream);
-            } catch (e) {
-                assert_unreached('Exception while creating MediaRecorder: ' + e);
-            }
+            var recorder = new MediaRecorder(stream);
             assert_equals(recorder.state, "inactive");
+            assert_equals(recorder.videoBitsPerSecond, 0);
+            assert_equals(recorder.audioBitsPerSecond, 0);
             test.done();
         });
 
-        var onError = test.step_func(function() {
-            assert_unreached('Error creating MediaRecorder.');
-        });
-
-        try {
-            navigator.webkitGetUserMedia(constraints, gotStream, onError);
-        } catch(e) {
-            assert_unreached('Exception launching getUserMedia(): ' + e);
-        }
+        const onError = test.unreached_func('Error creating MediaStream.');
+        navigator.webkitGetUserMedia(constraints, gotStream, onError);
     }, message);
 }
 
 function verifyVideoOnlyStream(stream) {
     assert_equals(stream.getAudioTracks().length, 0);
     assert_equals(stream.getVideoTracks().length, 1);
     assert_equals(stream.getVideoTracks()[0].readyState, 'live');
 }
 function verifyAudioOnlyStream(stream) {
     assert_equals(stream.getAudioTracks().length, 1);
     assert_equals(stream.getVideoTracks().length, 0);
     assert_equals(stream.getAudioTracks()[0].readyState, 'live');
 }
 function verifyAudioVideoStream(stream) {
     assert_equals(stream.getAudioTracks().length, 1);
     assert_equals(stream.getVideoTracks().length, 1);
     assert_equals(stream.getVideoTracks()[0].readyState, 'live');
     assert_equals(stream.getAudioTracks()[0].readyState, 'live');
 }
 
 // Note: webkitGetUserMedia() must be called with at least video or audio true.
 makeAsyncTest({video:true}, verifyVideoOnlyStream, 'Video only MediaRecorder');
 makeAsyncTest({audio:true}, verifyAudioOnlyStream, 'Audio only MediaRecorder');
 makeAsyncTest({audio:true, video:true}, verifyAudioVideoStream, 'Video and Audio MediaRecorder');
 
 </script>