[Sync] On disabling sync, device info records are removed.

components/sync/device_info/device_info_service_unittest.cc

 // Copyright 2015 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 "components/sync/device_info/device_info_service.h"
 
 #include <algorithm>
 #include <set>
 #include <utility>
 
@@ skipping 742 matching lines @@
 
   // Pointer address of metadata should remain constant because the processor
   // should not have been given new metadata.
   local_device()->Initialize(CreateDeviceInfo());
   base::RunLoop().RunUntilIdle();
   EXPECT_EQ(metadata, processor()->metadata());
 }
 
 TEST_F(DeviceInfoServiceTest, SendLocalData) {
   InitializeAndPump();
-  EXPECT_EQ(1, service()->CountActiveDevices());
   EXPECT_EQ(1, change_count());
   EXPECT_EQ(1u, processor()->put_multimap().size());
 
   ForcePulse();
-  EXPECT_EQ(1, service()->CountActiveDevices());
   EXPECT_EQ(2, change_count());
   EXPECT_EQ(2u, processor()->put_multimap().size());
 
+  // After clearing, pulsing should no-op and not result in a processor put or
+  // a notification to observers.
   local_device()->Clear();
   ForcePulse();
-  EXPECT_EQ(1, service()->CountActiveDevices());
   EXPECT_EQ(2, change_count());
   EXPECT_EQ(2u, processor()->put_multimap().size());
 }
 
+TEST_F(DeviceInfoServiceTest, DisableSync) {
+  InitializeAndPump();
+  EXPECT_EQ(1u, service()->GetAllDeviceInfo().size());
+  EXPECT_EQ(1, change_count());
+
+  DeviceInfoSpecifics specifics = GenerateTestSpecifics();
+  EntityChangeList add_changes;
+  PushBackEntityChangeAdd(specifics, &add_changes);
+  EXPECT_FALSE(
+      service()

[maxbogue, 2016/10/26 18:18:30]

nit: pull the error out onto a separate line to make it clearer?

[skym, 2016/10/26 18:24:35]

Done.

+          ->ApplySyncChanges(service()->CreateMetadataChangeList(), add_changes)
+          .IsSet());
+  EXPECT_EQ(2u, service()->GetAllDeviceInfo().size());
+  EXPECT_EQ(2, change_count());
+
+  // Should clear out all local data and notify observers.
+  service()->DisableSync();
+  EXPECT_EQ(0u, service()->GetAllDeviceInfo().size());
+  EXPECT_EQ(3, change_count());
+
+  // Reloading from storage shouldn't contain remote data.
+  RestartService();
+  EXPECT_EQ(1u, service()->GetAllDeviceInfo().size());
+  EXPECT_EQ(4, change_count());
+}
+
 }  // namespace
 
 }  // namespace syncer