Parse 'super' keyword.

src/parser.cc

Index: src/parser.cc
diff --git a/src/parser.cc b/src/parser.cc
index 6c941daa978d3d53bdc6cfca5f1914195bc7d2f0..e2677b5f0ec4afd0d978dc6f47456f19837e11ff 100644
--- a/src/parser.cc
+++ b/src/parser.cc
@@ -619,6 +619,12 @@ Expression* ParserTraits::ThisExpression(
   return factory->NewVariableProxy(scope->receiver(), pos);
 }
 
+Expression* ParserTraits::SuperReference(
+    Scope* scope, AstNodeFactory<AstConstructionVisitor>* factory, int pos) {
+  return factory->NewSuperReference(
+      ThisExpression(scope, factory, pos)->AsVariableProxy(),
+      pos);
+}
 
 Literal* ParserTraits::ExpressionFromLiteral(
     Token::Value token, int pos,
@@ -731,6 +737,7 @@ Parser::Parser(CompilationInfo* info)
   set_allow_generators(FLAG_harmony_generators);
   set_allow_arrow_functions(FLAG_harmony_arrow_functions);
   set_allow_harmony_numeric_literals(FLAG_harmony_numeric_literals);
+  set_allow_classes(FLAG_harmony_classes);
   for (int feature = 0; feature < v8::Isolate::kUseCounterFeatureCount;
        ++feature) {
     use_counts_[feature] = 0;