[es6] Remove Scanner and Parser flags for harmony_modules

src/preparser.h

Index: src/preparser.h
diff --git a/src/preparser.h b/src/preparser.h
index 3bd0953cb627122adaf0691918545a8034469ecb..6e34dfb620e7ac72d10886c778d7446b1121a5a2 100644
--- a/src/preparser.h
+++ b/src/preparser.h
@@ -130,10 +130,8 @@ class ParserBase : public Traits {
   ALLOW_ACCESSORS(legacy_const);
 #undef ALLOW_ACCESSORS
 
-  bool allow_harmony_modules() const { return scanner()->HarmonyModules(); }
   bool allow_harmony_unicode() const { return scanner()->HarmonyUnicode(); }
 
-  void set_allow_harmony_modules(bool a) { scanner()->SetHarmonyModules(a); }
   void set_allow_harmony_unicode(bool a) { scanner()->SetHarmonyUnicode(a); }
 
  protected:
@@ -313,7 +311,7 @@ class ParserBase : public Traits {
 
   Scope* NewScope(Scope* parent, ScopeType scope_type, FunctionKind kind) {
     DCHECK(ast_value_factory());
-    DCHECK(scope_type != MODULE_SCOPE || allow_harmony_modules());
+    DCHECK(scope_type != MODULE_SCOPE || FLAG_harmony_modules);
     DCHECK(!IsArrowFunction(kind) || scope_type == ARROW_SCOPE);
     Scope* result = new (zone())
         Scope(zone(), parent, scope_type, ast_value_factory(), kind);