Bug 899296 - Restore bytecode-level constant folding in lazily compiled functions. r=jorendorff.

js/src/frontend/Parser.cpp

@@ -2249,7 +2249,6 @@ Parser<FullParseHandler>::standaloneLazyFunction(HandleFunction fun, unsigned st
         return null();
     }
 
-
     if (fun->isNamedLambda()) {
         if (AtomDefnPtr p = pc->lexdeps->lookup(fun->name())) {
             Definition *dn = p.value().get<FullParseHandler>();
@@ -2263,6 +2262,9 @@ Parser<FullParseHandler>::standaloneLazyFunction(HandleFunction fun, unsigned st
     if (!pc->generateFunctionBindings(context, alloc, bindings))
         return null();
 
+    if (!FoldConstants(context, &pn, this))
+        return null();
+
     return pn;
 }