Fix TaskScheduler initialization in remoting processes.

remoting/host/it2me/it2me_native_messaging_host_main.cc

Index: remoting/host/it2me/it2me_native_messaging_host_main.cc
diff --git a/remoting/host/it2me/it2me_native_messaging_host_main.cc b/remoting/host/it2me/it2me_native_messaging_host_main.cc
index b6451dff9c5aedaae59f95469867d0048586c735..0bf0eefb2ced6525712549c7599485d9e00aeb39 100644
--- a/remoting/host/it2me/it2me_native_messaging_host_main.cc
+++ b/remoting/host/it2me/it2me_native_messaging_host_main.cc
@@ -200,6 +200,9 @@ int It2MeNativeMessagingHostMain(int argc, char** argv) {
   // Run the loop until channel is alive.
   run_loop.Run();
 
+  // Block until tasks blocking shutdown have completed their execution.
+  base::TaskScheduler::GetInstance()->Shutdown();
+
   return kSuccessExitCode;
 }