Revert "Add default subprotocol header"

This reverts commit d07c334.

src/ring/websocket/transit.clj

@@ -52,9 +52,7 @@
   are formatted using Transit. See: wrap-websocket-transit."
   [response]
   (if (contains? response :ring.websocket/listener)
-    (-> response
-        (update :ring.websocket/listener wrap-listener)
-        (update :ring.websocket/protocol #(or % "transit+json")))
+    (update response :ring.websocket/listener wrap-listener)
     response))
 
 (defn wrap-websocket-transit

test/ring/websocket/transit_test.clj

@@ -85,21 +85,6 @@
               [:listener/ping :yyy]
               [:listener/error :eee]]
              @log))))
-  (testing "subprotocol header set"
-    (let [handler  (wst/wrap-websocket-transit
-                    (fn [_]
-                      {:ring.websocket/listener (reify wsp/Listener)}))
-          response (handler {})]
-      (is (= "transit+json"
-             (:ring.websocket/protocol response)))))
-  (testing "subprotocol header not overridden"
-    (let [handler  (wst/wrap-websocket-transit
-                    (fn [_]
-                      {:ring.websocket/listener (reify wsp/Listener)
-                       :ring.websocket/protocol "custom"}))
-          response (handler {})]
-      (is (= "custom"
-             (:ring.websocket/protocol response)))))
   (testing "parsing exceptions trigger on-error"
     (let [log      (atom [])
           socket   (reify wsp/Socket)