[Sync] Rework Invalidator-related unit tests

sync/internal_api/public/base/invalidation_state.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef SYNC_INTERNAL_API_PUBLIC_BASE_INVALIDATION_STATE_H_
 #define SYNC_INTERNAL_API_PUBLIC_BASE_INVALIDATION_STATE_H_
 
 #include <string>
 
+#include "base/memory/scoped_ptr.h"
+
+namespace base {
+class DictionaryValue;
+class Value;
+}  // namespace
+
 namespace syncer {
 
 // Opaque class that represents an ack handle.
 // TODO(dcheng): This is just a refactoring change, so the class is empty for
 // the moment. It will be filled once we start implementing 'reminders'.
 class AckHandle {
+ public:
+  bool Equals(const AckHandle& other) const;
+
+  scoped_ptr<base::Value> ToValue() const;
+
+  bool ResetFromValue(const base::Value& value);
 };
 
 struct InvalidationState {
   std::string payload;
   AckHandle ack_handle;
+
+  bool Equals(const InvalidationState& other) const;
+
+  // Caller owns the returned DictionaryValue.
+  scoped_ptr<base::DictionaryValue> ToValue() const;
+
+  bool ResetFromValue(const base::DictionaryValue& value);
 };
 
 }  // namespace syncer
 
 #endif  // SYNC_INTERNAL_API_PUBLIC_BASE_INVALIDATION_STATE_H_