switch away from goog.provide as Closure checks for this, use

goog/constructNamespace_ for now. While it would seem to make
sense to just goog.provide cljs.user in cljs.core, this will likely
cause trouble later when we support files without namespaces
(which will likely all live under cljs.user)

Author: swannodette

src/main/cljs/clojure/browser/repl.cljs

@@ -120,7 +120,7 @@
     ;; suppress useless Google Closure error about duplicate provides
     (set! (.-isProvided_ js/goog) (fn [name] false))
     ;; provide cljs.user
-    (goog/provide "cljs.user")
+    (goog/constructNamespace_ "cljs.user")
     (set! (.-writeScriptTag__ js/goog)
       (fn [src opt_sourceText]
         ;; the page is already loaded, we can no longer leverage document.write