[strong] Implement static restrictions on binding 'undefined' in arrow functions

src/preparser.cc

Index: src/preparser.cc
diff --git a/src/preparser.cc b/src/preparser.cc
index d4515fcb51d9b8c555daf52457a4a63c209ec747..a02305ffd206bb0a0b5097e9961685cd52c7d5b2 100644
--- a/src/preparser.cc
+++ b/src/preparser.cc
@@ -916,12 +916,12 @@ PreParser::Expression PreParser::ParseFunctionLiteral(
   // We don't yet know if the function will be strict, so we cannot yet produce
   // errors for parameter names or duplicates. However, we remember the
   // locations of these errors if they occur and produce the errors later.
-  Scanner::Location eval_args_error_loc = Scanner::Location::invalid();
-  Scanner::Location dupe_error_loc = Scanner::Location::invalid();
-  Scanner::Location reserved_error_loc = Scanner::Location::invalid();
+  Scanner::Location eval_args_loc = Scanner::Location::invalid();
+  Scanner::Location dupe_loc = Scanner::Location::invalid();
+  Scanner::Location reserved_loc = Scanner::Location::invalid();
 
   // Similarly for strong mode.
-  Scanner::Location undefined_error_loc = Scanner::Location::invalid();
+  Scanner::Location undefined_loc = Scanner::Location::invalid();
 
   bool is_rest = false;
   bool done = arity_restriction == FunctionLiteral::GETTER_ARITY ||
@@ -936,20 +936,20 @@ PreParser::Expression PreParser::ParseFunctionLiteral(
 
     Identifier param_name =
         ParseIdentifierOrStrictReservedWord(&is_strict_reserved, CHECK_OK);
-    if (!eval_args_error_loc.IsValid() && param_name.IsEvalOrArguments()) {
-      eval_args_error_loc = scanner()->location();
+    if (!eval_args_loc.IsValid() && param_name.IsEvalOrArguments()) {
+      eval_args_loc = scanner()->location();
     }
-    if (!undefined_error_loc.IsValid() && param_name.IsUndefined()) {
-      undefined_error_loc = scanner()->location();
+    if (!undefined_loc.IsValid() && param_name.IsUndefined()) {
+      undefined_loc = scanner()->location();
     }
-    if (!reserved_error_loc.IsValid() && is_strict_reserved) {
-      reserved_error_loc = scanner()->location();
+    if (!reserved_loc.IsValid() && is_strict_reserved) {
+      reserved_loc = scanner()->location();
     }
 
     int prev_value = scanner()->FindSymbol(&duplicate_finder, 1);
 
-    if (!dupe_error_loc.IsValid() && prev_value != 0) {
-      dupe_error_loc = scanner()->location();
+    if (!dupe_loc.IsValid() && prev_value != 0) {
+      dupe_loc = scanner()->location();
     }
 
     if (arity_restriction == FunctionLiteral::SETTER_ARITY) break;
@@ -984,9 +984,8 @@ PreParser::Expression PreParser::ParseFunctionLiteral(
   CheckFunctionName(language_mode(), kind, function_name,
                     name_is_strict_reserved, function_name_location, CHECK_OK);
   const bool use_strict_params = is_rest || IsConciseMethod(kind);
-  CheckFunctionParameterNames(language_mode(), use_strict_params,
-                              eval_args_error_loc, undefined_error_loc,
-                              dupe_error_loc, reserved_error_loc, CHECK_OK);
+  CheckFunctionParameterNames(language_mode(), use_strict_params, eval_args_loc,
+                              undefined_loc, dupe_loc, reserved_loc, CHECK_OK);
 
   if (is_strict(language_mode())) {
     int end_position = scanner()->location().end_pos;