Sloppy-mode let parsing

src/preparser.cc

Index: src/preparser.cc
diff --git a/src/preparser.cc b/src/preparser.cc
index 7e75e78ef9c2e0753c26e6f8bf9f5303ddc02f70..6d665680c9c50580a7359ccbbb0d31c0a0bf6cab 100644
--- a/src/preparser.cc
+++ b/src/preparser.cc
@@ -199,7 +199,7 @@ PreParser::Statement PreParser::ParseStatementListItem(bool* ok) {
       }
       break;
     case Token::LET:
-      if (allow_let()) {
+      if (IsNextLetKeyword()) {
         return ParseVariableStatement(kStatementListItem, ok);
       }
       break;
@@ -893,7 +893,7 @@ 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();