[gnome-builder] rust-langserv: set self._supervisor

[Christian Hergert <chergert src gnome org>]

commit 72bc6212c5eeb2c6ff8eac691776194dc4477ff4
Author: Christian Hergert <chergert redhat com>
Date:   Sat Oct 29 21:15:27 2016 -0700

    rust-langserv: set self._supervisor
    
    We were checking for this but never assigned it.

 plugins/rust-langserv/rust_langserv_plugin.py |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)
---
diff --git a/plugins/rust-langserv/rust_langserv_plugin.py b/plugins/rust-langserv/rust_langserv_plugin.py
index 636e402..23338f3 100644
--- a/plugins/rust-langserv/rust_langserv_plugin.py
+++ b/plugins/rust-langserv/rust_langserv_plugin.py
@@ -91,10 +91,10 @@ class RustService(Ide.Object, Ide.Service):
 
             # Spawn our peer process and monitor it for
             # crashes. We may need to restart it occasionally.
-            supervisor = Ide.SubprocessSupervisor()
-            supervisor.connect('spawned', self._rls_spawned)
-            supervisor.set_launcher(launcher)
-            supervisor.start()
+            self._supervisor = Ide.SubprocessSupervisor()
+            self._supervisor.connect('spawned', self._rls_spawned)
+            self._supervisor.set_launcher(launcher)
+            self._supervisor.start()
 
     def _rls_spawned(self, supervisor, subprocess):
         """