Add InvalidationStateTracker::Forget() to erase an entry from storage.

sync/notifier/registration_manager_unittest.cc

 // 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.
 
 #include "sync/notifier/registration_manager.h"
 
 #include <algorithm>
 #include <cmath>
 #include <cstddef>
 #include <deque>
@@ skipping 220 matching lines @@
 };
 
 // Basic test of UpdateRegisteredIds to make sure we properly register
 // new IDs and unregister any IDs no longer in the set.
 TEST_F(RegistrationManagerTest, UpdateRegisteredIds) {
   ObjectIdSet ids = GetSequenceOfIds(kObjectIdsCount - 1);
 
   EXPECT_TRUE(fake_registration_manager_.GetRegisteredIdsForTest().empty());
   EXPECT_TRUE(fake_invalidation_client_.GetRegisteredIdsForTest().empty());
 
-  fake_registration_manager_.UpdateRegisteredIds(ids);
+  ObjectIdSet expected_unregistered_ids;
+
+  ObjectIdSet unregistered_ids =
+      fake_registration_manager_.UpdateRegisteredIds(ids);
+  EXPECT_EQ(expected_unregistered_ids, unregistered_ids);
   EXPECT_EQ(ids, fake_registration_manager_.GetRegisteredIdsForTest());
   EXPECT_EQ(ids, fake_invalidation_client_.GetRegisteredIdsForTest());
 
   ids.insert(GetIdForIndex(kObjectIdsCount - 1));
   ids.erase(GetIdForIndex(kObjectIdsCount - 2));
-  fake_registration_manager_.UpdateRegisteredIds(ids);
+  unregistered_ids = fake_registration_manager_.UpdateRegisteredIds(ids);
+  expected_unregistered_ids.insert(GetIdForIndex(kObjectIdsCount - 2));
+  EXPECT_EQ(expected_unregistered_ids, unregistered_ids);
   EXPECT_EQ(ids, fake_registration_manager_.GetRegisteredIdsForTest());
   EXPECT_EQ(ids, fake_invalidation_client_.GetRegisteredIdsForTest());
 }
 
 int GetRoundedBackoff(double retry_interval, double jitter) {
   const double kInitialRetryInterval = 3.0;
   const double kMinRetryInterval = 2.0;
   const double kMaxRetryInterval = 20.0;
   const double kBackoffExponent = 2.0;
   const double kMaxJitter = 0.5;
@@ skipping 158 matching lines @@
       fake_registration_manager_.GetPendingRegistrationsForTest());
 
   fake_registration_manager_.MarkAllRegistrationsLost();
   ExpectPendingRegistrations(
       enabled_ids, 0.0,
       fake_registration_manager_.GetPendingRegistrationsForTest());
 }
 
 }  // namespace
 }  // namespace syncer