Fix crash when setting breakpoint in Observatory

runtime/vm/object.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/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/cpu.h"
@@ skipping 3327 matching lines @@
 
 
 void Class::set_token_pos(TokenPosition token_pos) const {
   ASSERT(!token_pos.IsClassifying());
   StoreNonPointer(&raw_ptr()->token_pos_, token_pos);
 }
 
 
 TokenPosition Class::ComputeEndTokenPos() const {
   // Return the begin token for synthetic classes.
-  if (IsMixinApplication() || IsTopLevel()) {
+  if (is_synthesized_class() || IsMixinApplication() || IsTopLevel()) {
     return token_pos();
   }
   const Script& scr = Script::Handle(script());
   ASSERT(!scr.IsNull());
   const TokenStream& tkns = TokenStream::Handle(scr.tokens());
   TokenStream::Iterator tkit(tkns,
                              token_pos(),
                              TokenStream::Iterator::kNoNewlines);
   intptr_t level = 0;
   while (tkit.CurrentTokenKind() != Token::kEOS) {
@@ skipping 18517 matching lines @@
   return UserTag::null();
 }
 
 
 const char* UserTag::ToCString() const {
   const String& tag_label = String::Handle(label());
   return tag_label.ToCString();
 }
 
 }  // namespace dart