Restore connectionDebugInfo().

This can't use self._connectionMap, because it needs to
know the version associated with each connection.

src/ZODB/DB.py

@@ -562,7 +562,8 @@ class DB(object):
     def connectionDebugInfo(self):
         result = []
         t = time()
-        def f(c):
+        for version, pool in self._pools.items():
+            for c in pool.all_as_list():
                 o = c._opened
                 d = c._debug_info
                 if d:
@@ -577,8 +578,6 @@ class DB(object):
                     'info': d,
                     'version': version,
                     })
-
-        self._connectionMap(f)
         return result
 
     def getActivityMonitor(self):