Scanner: disallow unicode escapes in regexp flags.

src/scanner.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.
 
 // Features shared by parsing and pre-parsing scanners.
 
 #include <stdint.h>
 
 #include <cmath>
 
@@ skipping 1120 matching lines @@
     }
   }
   Advance();  // consume '/'
 
   literal.Complete();
 
   return true;
 }
 
 
-bool Scanner::ScanLiteralUnicodeEscape() {
-  DCHECK(c0_ == '\\');
-  AddLiteralChar(c0_);
-  Advance();
-  int hex_digits_read = 0;
-  if (c0_ == 'u') {
-    AddLiteralChar(c0_);
-    while (hex_digits_read < 4) {
-      Advance();
-      if (!IsHexDigit(c0_)) break;
-      AddLiteralChar(c0_);
-      ++hex_digits_read;
-    }
-  }
-  return hex_digits_read == 4;
-}
-
-
 bool Scanner::ScanRegExpFlags() {
   // Scan regular expression flags.
   LiteralScope literal(this);
   while (c0_ >= 0 && unicode_cache_->IsIdentifierPart(c0_)) {
     if (c0_ != '\\') {
       AddLiteralCharAdvance();
     } else {
-      if (!ScanLiteralUnicodeEscape()) {
-        return false;
-      }
-      Advance();
+      return false;
     }
   }
   literal.Complete();
 
   next_.location.end_pos = source_pos() - 1;
   return true;
 }
 
 
 const AstRawString* Scanner::CurrentSymbol(AstValueFactory* ast_value_factory) {
@@ skipping 167 matching lines @@
     }
     backing_store_.Add(static_cast<uint8_t>((one_byte_length >> 7) | 0x80u));
   }
   backing_store_.Add(static_cast<uint8_t>(one_byte_length & 0x7f));
 
   backing_store_.AddBlock(bytes);
   return backing_store_.EndSequence().start();
 }
 
 } }  // namespace v8::internal