CLJS-1417: cljs.js: require macros failure error message pertains to non-macros

Adds and uses a new analyzer error message specifically
for the failure to load a macros ns.

Author: mfikes

src/main/cljs/cljs/js.cljs

@@ -223,7 +223,9 @@
                              (str "Invalid :lang specified " lang ", only :clj or :js allowed"))))))
                  (cb (wrap-error
                        (ana/error env
-                         (ana/error-message :undeclared-ns
+                         (ana/error-message (if (:macros-ns opts)
+                                              :undeclared-macros-ns
+                                              :undeclared-ns)
                            {:ns-sym name :js-provide (cljs.core/name name)})))))))
            (catch :default cause
              (cb (wrap-error

src/main/clojure/cljs/analyzer.cljc

@@ -228,6 +228,12 @@
        ", " (ns->relpath ns-sym :cljc)
        ", or Closure namespace \"" js-provide "\""))
 
+(defmethod error-message :undeclared-macros-ns
+  [warning-type {:keys [ns-sym js-provide] :as info}]
+  (str "No such macros namespace: " ns-sym
+       ", could not locate " (ns->relpath ns-sym :clj)
+       " or " (ns->relpath ns-sym :cljc)))
+
 (defmethod error-message :dynamic
   [warning-type info]
   (str (:name info) " not declared ^:dynamic"))