Revert "Factor formal argument parsing into ParserBase"

src/preparser.cc

Index: src/preparser.cc
diff --git a/src/preparser.cc b/src/preparser.cc
index daec9bfb25f3bfafd80a12a92289257569d9615d..4371cdb27b1c703d001937296774e5135eec9169 100644
--- a/src/preparser.cc
+++ b/src/preparser.cc
@@ -926,19 +926,62 @@ PreParser::Expression PreParser::ParseFunctionLiteral(
   PreParserFactory factory(NULL);
   FunctionState function_state(&function_state_, &scope_, function_scope, kind,
                                &factory);
-  FormalParameterErrorLocations error_locs;
+  //  FormalParameterList ::
+  //    '(' (Identifier)*[','] ')'
+  Expect(Token::LPAREN, CHECK_OK);
+  int start_position = position();
+  DuplicateFinder duplicate_finder(scanner()->unicode_cache());
+  // 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_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_loc = Scanner::Location::invalid();
 
   bool is_rest = false;
-  Expect(Token::LPAREN, CHECK_OK);
-  int start_position = scanner()->location().beg_pos;
-  PreParserFormalParameterList params =
-      ParseFormalParameterList(&error_locs, &is_rest, CHECK_OK);
-  Expect(Token::RPAREN, CHECK_OK);
-  int formals_end_position = scanner()->location().end_pos;
+  bool done = arity_restriction == FunctionLiteral::GETTER_ARITY ||
+      (peek() == Token::RPAREN &&
+       arity_restriction != FunctionLiteral::SETTER_ARITY);
+  while (!done) {
+    bool is_strict_reserved = false;
+    is_rest = peek() == Token::ELLIPSIS && allow_harmony_rest_params();
+    if (is_rest) {
+      Consume(Token::ELLIPSIS);
+    }
+
+    Identifier param_name =
+        ParseIdentifierOrStrictReservedWord(&is_strict_reserved, CHECK_OK);
+    if (!eval_args_loc.IsValid() && param_name.IsEvalOrArguments()) {
+      eval_args_loc = scanner()->location();
+    }
+    if (!undefined_loc.IsValid() && param_name.IsUndefined()) {
+      undefined_loc = scanner()->location();
+    }
+    if (!reserved_loc.IsValid() && is_strict_reserved) {
+      reserved_loc = scanner()->location();
+    }
 
-  CheckArityRestrictions(params->length(), arity_restriction, start_position,
-                         formals_end_position, ok);
-  if (!*ok) return Expression::Default();
+    int prev_value = scanner()->FindSymbol(&duplicate_finder, 1);
+
+    if (!dupe_loc.IsValid() && prev_value != 0) {
+      dupe_loc = scanner()->location();
+    }
+
+    if (arity_restriction == FunctionLiteral::SETTER_ARITY) break;
+    done = (peek() == Token::RPAREN);
+    if (!done) {
+      if (is_rest) {
+        ReportMessageAt(scanner()->peek_location(), "param_after_rest");
+        *ok = false;
+        return Expression::Default();
+      }
+      Expect(Token::COMMA, CHECK_OK);
+    }
+  }
+  Expect(Token::RPAREN, CHECK_OK);
 
   // See Parser::ParseFunctionLiteral for more information about lazy parsing
   // and lazy compilation.
@@ -959,8 +1002,8 @@ 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, error_locs,
-                              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;