Provide access to the ID for the remoted Windows session in the network process

remoting/host/ipc_desktop_environment.cc

Index: remoting/host/ipc_desktop_environment.cc
diff --git a/remoting/host/ipc_desktop_environment.cc b/remoting/host/ipc_desktop_environment.cc
index a5bb70f1b6937a3d36eb2c229ba8aac11dfda5a4..884bd19ace6babd5b55064667ceac4d0f91b4e54 100644
--- a/remoting/host/ipc_desktop_environment.cc
+++ b/remoting/host/ipc_desktop_environment.cc
@@ -73,6 +73,10 @@ void IpcDesktopEnvironment::SetCapabilities(const std::string& capabilities) {
   return desktop_session_proxy_->SetCapabilities(capabilities);
 }
 
+uint32_t IpcDesktopEnvironment::GetDesktopSessionId() const {
+  return desktop_session_proxy_->desktop_session_id();
+}
+
 IpcDesktopEnvironmentFactory::IpcDesktopEnvironmentFactory(
     scoped_refptr<base::SingleThreadTaskRunner> audio_task_runner,
     scoped_refptr<base::SingleThreadTaskRunner> caller_task_runner,