CLJS-2893: seq: use .-length instead of alength for strings

Author: olieidel

src/main/cljs/cljs/core.cljs

@@ -1214,7 +1214,7 @@
         (IndexedSeq. coll 0 nil))
 
       (string? coll)
-      (when-not (zero? (alength coll))
+      (when-not (zero? (.-length coll))
         (IndexedSeq. coll 0 nil))
 
       (native-satisfies? ISeqable coll)