A decimal integer literal with a leading 0 is now an error in strict mode.

src/parsing/preparser.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <cmath>
 
 #include "src/allocation.h"
 #include "src/base/logging.h"
 #include "src/conversions-inl.h"
 #include "src/conversions.h"
@@ skipping 144 matching lines @@
           is_sloppy(function_scope->language_mode()) && formals.is_simple &&
           !IsConciseMethod(kind);
       ValidateFormalParameters(function_scope->language_mode(),
                                allow_duplicate_parameters,
                                CHECK_OK_VALUE(kPreParseSuccess));
     }
 
     if (is_strict(function_scope->language_mode())) {
       int end_pos = scanner()->location().end_pos;
       CheckStrictOctalLiteral(function_scope->start_position(), end_pos, ok);
-      CheckDecimalLiteralWithLeadingZero(function_scope->start_position(),
-                                         end_pos);
     }
   }
   return kPreParseSuccess;
 }
 
 
 // Preparsing checks a JavaScript program and emits preparse-data that helps
 // a later parsing to be faster.
 // See preparser-data.h for the data.
 
@@ skipping 53 matching lines @@
   // function, since the function can declare itself strict.
   CheckFunctionName(language_mode, function_name, function_name_validity,
                     function_name_location, CHECK_OK);
   const bool allow_duplicate_parameters =
       is_sloppy(language_mode) && formals.is_simple && !IsConciseMethod(kind);
   ValidateFormalParameters(language_mode, allow_duplicate_parameters, CHECK_OK);
 
   int end_position = scanner()->location().end_pos;
   if (is_strict(language_mode)) {
     CheckStrictOctalLiteral(start_position, end_position, CHECK_OK);
-    CheckDecimalLiteralWithLeadingZero(start_position, end_position);
   }
   function_scope->set_end_position(end_position);
 
   if (FLAG_trace_preparse) {
     PrintF("  [%s]: %i-%i\n",
            track_unresolved_variables_ ? "Preparse resolution"
                                        : "Preparse no-resolution",
            function_scope->start_position(), function_scope->end_position());
   }
 
@@ skipping 67 matching lines @@
     }
   }
 }
 
 #undef CHECK_OK
 #undef CHECK_OK_CUSTOM
 
 
 }  // namespace internal
 }  // namespace v8