[Media Router] Conditionally enable mDNS on Windows.

chrome/browser/media/router/media_router_mojo_test.cc

Index: chrome/browser/media/router/media_router_mojo_test.cc
diff --git a/chrome/browser/media/router/media_router_mojo_test.cc b/chrome/browser/media/router/media_router_mojo_test.cc
index 1b8869f836b4435742e1135dde599b2a130ef51e..730cbbcb34af6093404712daa1e3fa8cd0d7fcf8 100644
--- a/chrome/browser/media/router/media_router_mojo_test.cc
+++ b/chrome/browser/media/router/media_router_mojo_test.cc
@@ -28,8 +28,7 @@ MockMediaRouteProvider::~MockMediaRouteProvider() {
 
 MediaRouterMojoTest::MediaRouterMojoTest()
     : extension_id_("ext-123"),
-      mock_media_router_(new MediaRouterMojoImpl(&mock_event_page_tracker_)),
-      message_loop_(mojo::common::MessagePumpMojo::Create()) {
+      mock_media_router_(new MediaRouterMojoImpl(&mock_event_page_tracker_)) {
   mock_media_router_->set_instance_id_for_test(kInstanceId);
 }
 
@@ -56,11 +55,11 @@ void MediaRouterMojoTest::SetUp() {
   ON_CALL(mock_event_page_tracker_, IsEventPageSuspended(extension_id_))
       .WillByDefault(testing::Return(false));
   ConnectProviderManagerService();
-  message_loop_.RunUntilIdle();
+  base::RunLoop().RunUntilIdle();
 }
 
 void MediaRouterMojoTest::ProcessEventLoop() {
-  message_loop_.RunUntilIdle();
+  base::RunLoop().RunUntilIdle();
 }
 
 }  // namespace media_router