Revert "Lol, don't use `maybe_open_feed()` for now, it's totally borked..."

Think this was fixed by passing through `**kwargs` in
`maybe_open_feed()`, the shielding for fsp respawns wasn't being
properly passed through..

This reverts commit 2f1455d423.

piker/clearing/_ems.py

@@ -32,7 +32,7 @@ import tractor
 
 from ..log import get_logger
 from ..data._normalize import iterticks
-from ..data.feed import Feed, maybe_open_feed, open_feed
+from ..data.feed import Feed, maybe_open_feed
 from .._daemon import maybe_spawn_brokerd
 from . import _paper_engine as paper
 from ._messages import (
@@ -958,17 +958,13 @@ async def _emsd_main(
 
     # spawn one task per broker feed
     async with (
-        open_feed(
-        # maybe_open_feed(
+        maybe_open_feed(
             broker,
             [symbol],
             loglevel=loglevel,
-        # ) as (feed, stream),
-        ) as feed,
+        ) as (feed, stream),
     ):
 
-        stream = feed.stream
-
         # XXX: this should be initial price quote from target provider
         first_quote = feed.first_quote
 

piker/fsp/__init__.py

@@ -177,15 +177,11 @@ async def cascade(
     func: Callable = _fsps[fsp_func_name]
 
     # open a data feed stream with requested broker
-    # async with data.feed.maybe_open_feed(
-    async with data.feed.open_feed(
+    async with data.feed.maybe_open_feed(
         brokername,
         [symbol],
         shielded_stream=True,
-    # ) as (feed, stream):
-    ) as feed:
-
-        stream = feed.stream
+    ) as (feed, stream):
 
         assert src.token == feed.shm.token