Compute accurate token count when loading from snapshot

runtime/vm/parser.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/parser.h"
 
 #include "lib/invocation_mirror.h"
 #include "platform/utils.h"
 #include "vm/ast_transformer.h"
 #include "vm/bootstrap.h"
@@ skipping 425 matching lines @@
   return current_class_;
 }
 
 
 void Parser::set_current_class(const Class& value) {
   current_class_ = value.raw();
 }
 
 
 void Parser::SetPosition(intptr_t position) {
-  if (position < TokenPos() && position != 0) {
-    INC_STAT(I, num_tokens_rewind, (TokenPos() - position));
-  }
   tokens_iterator_.SetCurrentPosition(position);
   token_kind_ = Token::kILLEGAL;
 }
 
 
 void Parser::ParseCompilationUnit(const Library& library,
                                   const Script& script) {
   Isolate* isolate = Isolate::Current();
   ASSERT(isolate->long_jump_base()->IsSafeToJump());
   CSTAT_TIMER_SCOPE(isolate, parser_timer);
@@ skipping 13019 matching lines @@
 void Parser::SkipQualIdent() {
   ASSERT(IsIdentifier());
   ConsumeToken();
   if (CurrentToken() == Token::kPERIOD) {
     ConsumeToken();  // Consume the kPERIOD token.
     ExpectIdentifier("identifier expected after '.'");
   }
 }
 
 }  // namespace dart