Made parser not accept unicode escapes inside "native" when used as a keyword.

src/parser.cc

Index: src/parser.cc
diff --git a/src/parser.cc b/src/parser.cc
index 1318dc928dd6659d664e8ed82bd63e49c852393c..334839184ee3fffefcf8cdebf3bd2e8defc1e575 100644
--- a/src/parser.cc
+++ b/src/parser.cc
@@ -1780,7 +1780,8 @@ Statement* Parser::ParseExpressionOrLabelledStatement(ZoneStringList* labels,
       expr != NULL &&
       expr->AsVariableProxy() != NULL &&
       expr->AsVariableProxy()->name()->Equals(
-          isolate()->heap()->native_symbol())) {
+          isolate()->heap()->native_symbol()) &&
+      !scanner().literal_contains_escapes()) {
     return ParseNativeDeclaration(ok);
   }