Fix render ratom watches being lost for class components with StrictMode

Same as #640

Author: Deraen

src/reagent/impl/component.cljs

@@ -193,13 +193,25 @@
 
     :componentDidMount
     (fn componentDidMount []
-      (this-as c (.call f c c)))
+      (this-as c
+        (when (.-cleanup-queued ^clj c)
+          (set! (.-cleanup-cancelled ^clj c) true)
+          (set! (.-cleanup-queued ^clj c) false))
+        (when-not (nil? f)
+          (.call f c c))))
 
     :componentWillUnmount
     (fn componentWillUnmount []
       (this-as c
-               (some-> (gobj/get c "cljsRatom") ratom/dispose!)
-               (batch/mark-rendered c)
+               ;; (some-> (gobj/get c "cljsRatom") ratom/dispose!)
+               (set! (.-cleanup-cancelled ^clj c) false)
+               (set! (.-cleanup-queued ^clj c) true)
+               (.then (.resolve js/Promise nil)
+                      (fn []
+                        (when (false? (.-cleanup-cancelled ^clj c))
+                          (set! (.-cleanup-queued ^clj c) false)
+                          (batch/mark-rendered c)
+                          (some-> (gobj/get c "cljsRatom") ratom/dispose!))))
                (when-not (nil? f)
                  (.call f c c))))
 
@@ -218,6 +230,7 @@
 ;; Though the value is nil here, the wrapper function will be
 ;; added to class to manage Reagent ratom lifecycle.
 (def obligatory {:shouldComponentUpdate nil
+                 :componentDidMount nil
                  :componentWillUnmount nil})
 
 (def dash-to-method-name (util/memoize-1 util/dash-to-method-name))