Extend components/test_runner's generated WebMediaStream to have a Chrome VideoTrack and Source

components/html_viewer/web_test_delegate_impl.cc

Index: components/html_viewer/web_test_delegate_impl.cc
diff --git a/components/html_viewer/web_test_delegate_impl.cc b/components/html_viewer/web_test_delegate_impl.cc
index 4e958fdaf3b59cbbce1da69c694f7450c34344a6..b2dceeca35485510afc5699b52ee4a4e2e696710 100644
--- a/components/html_viewer/web_test_delegate_impl.cc
+++ b/components/html_viewer/web_test_delegate_impl.cc
@@ -310,6 +310,12 @@ void WebTestDelegateImpl::ResetPermissions() {
   NOTIMPLEMENTED();
 }
 
+bool WebTestDelegateImpl::AddMediaStreamSourceAndTrack(
+    blink::WebMediaStream* stream) {
+  NOTIMPLEMENTED();
+  return false;
+}
+
 cc::SharedBitmapManager* WebTestDelegateImpl::GetSharedBitmapManager() {
   NOTIMPLEMENTED();
   return nullptr;