Prefer unlinking in test rather than test only start.

The more similar the code used in test is to production, the better.
If the test needs to survive killing the manager, unlink can be used.

src/riak_core_bg_manager.erl

@@ -103,9 +103,7 @@
          get_token/2,
          get_token/3,
          token_info/0,
-         token_info/1,
-         %% Testing
-         start/0
+         token_info/1
         ]).
 
 %% reporting
@@ -139,11 +137,6 @@ start_link() ->
     _ = maybe_create_ets(),
     gen_server:start_link({local, ?SERVER}, ?MODULE, [], []).
 
-%% Test entry point to start stand-alone server
-start() ->
-    _ = maybe_create_ets(),
-    gen_server:start({local, ?SERVER}, ?MODULE, [], []).
-
 %% @doc Global kill switch - causes all locks/tokens to be given out freely without limits.
 %% Nothing will be tracked or recorded.
 -spec bypass(boolean()) -> ok.

test/bg_manager_tests.erl

@@ -146,12 +146,14 @@ verify_token_rates() ->
 %% doesn't take down our test too.
 start_bg_mgr() ->
     %% setup with history window to 1 seconds
-    ?BG_MGR:start(),
+    {ok, Pid} = ?BG_MGR:start_link(),
+    unlink(Pid),
     timer:sleep(100).
 
 kill_bg_mgr() ->
     Pid = erlang:whereis(?BG_MGR),
     ?assertNot(Pid == undefined),
+    unlink(Pid),
     erlang:exit(Pid, kill).
 
 crash_and_restart_token_manager() ->