Simplify Scanner bookmarking.

test/cctest/parsing/test-scanner.cc

 // Copyright 2016 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.
 
 // Tests v8::internal::Scanner. Note that presently most unit tests for the
 // Scanner are in cctest/test-parsing.cc, rather than here.
 
 #include "src/handles-inl.h"
 #include "src/parsing/scanner-character-streams.h"
 #include "src/parsing/scanner.h"
@@ skipping 38 matching lines @@
     auto scanner = make_scanner(src_simple);
     Scanner::BookmarkScope bookmark(scanner.get());
 
     for (size_t i = 0; i < std::min(bookmark_pos + 10, tokens.size()); i++) {
       if (i == bookmark_pos) {
         bookmark.Set();
       }
       DCHECK_EQ(tokens[i], scanner->Next());
     }
 
-    bookmark.Reset();
+    bookmark.Apply();
     for (size_t i = bookmark_pos; i < tokens.size(); i++) {
       DCHECK_EQ(tokens[i], scanner->Next());
     }
   }
 }