Alway teardown quote gen on exit

piker/ui/monitor.py

@@ -140,8 +140,6 @@ async def update_quotes(
         log.debug("Waiting on quotes")
 
     log.warn("Data feed connection dropped")
-    # XXX: if we're cancelled this should never get called
-    # nursery.cancel_scope.cancel()
 
 
 async def stream_symbol_selection():
@@ -227,7 +225,6 @@ async def _async_main(
     table.bind(minimum_height=table.setter('height'))
 
     ss = tractor.current_actor().statespace
-    try:
     async with trio.open_nursery() as nursery:
         pager = PagerView(
             container=box,
@@ -253,12 +250,11 @@ async def _async_main(
             feed._symbol_data_cache,
             quotes
         )
-
+        try:
             # Trio-kivy entry point.
             await async_runTouchApp(widgets['root'])  # run kivy
+        finally:
+            # cancel remote data feed task
+            await quote_gen.aclose()
             # cancel GUI update task
             nursery.cancel_scope.cancel()
-    finally:
-        with trio.open_cancel_scope(shield=True):
-            # cancel aysnc gen call
-            await quote_gen.aclose()