Sloppy-mode let parsing

src/preparser.cc

Index: src/preparser.cc
diff --git a/src/preparser.cc b/src/preparser.cc
index b1541f616afe133554881e99aec4f71a9f5e45e0..c83250d73e9041e9c60ad48e0b1f36ac01f9695f 100644
--- a/src/preparser.cc
+++ b/src/preparser.cc
@@ -198,7 +198,7 @@ PreParser::Statement PreParser::ParseStatementListItem(bool* ok) {
       }
       break;
     case Token::LET:
-      if (allow_let()) {
+      if (IsNextLetKeyword()) {
         return ParseVariableStatement(kStatementListItem, ok);
       }
       break;
@@ -874,7 +874,7 @@ PreParser::Statement PreParser::ParseForStatement(bool* ok) {
   if (peek() != Token::SEMICOLON) {
     ForEachStatement::VisitMode mode;
     if (peek() == Token::VAR || (peek() == Token::CONST && allow_const()) ||
-        (peek() == Token::LET && allow_let())) {
+        (peek() == Token::LET && IsNextLetKeyword())) {
       int decl_count;
       Scanner::Location first_initializer_loc = Scanner::Location::invalid();
       Scanner::Location bindings_loc = Scanner::Location::invalid();