Parser: reuse has_extends, instead of doing a check again

src/parsing/parser.cc

Index: src/parsing/parser.cc
diff --git a/src/parsing/parser.cc b/src/parsing/parser.cc
index 8164c7d3b2cda7e9dd5af74dac0883f0ff95541e..f2be740189b603a2f4b23480107d0cc8d1883243 100644
--- a/src/parsing/parser.cc
+++ b/src/parsing/parser.cc
@@ -4970,7 +4970,7 @@ ClassLiteral* Parser::ParseClassLiteral(ExpressionClassifier* classifier,
   int end_pos = scanner()->location().end_pos;
 
   if (constructor == NULL) {
-    constructor = DefaultConstructor(name, extends != NULL, block_scope, pos,
+    constructor = DefaultConstructor(name, has_extends, block_scope, pos,
                                      end_pos, block_scope->language_mode());
   }