Add Statistics for SupervisedUserSettingService during merging and syncing data.

chrome/browser/supervised_user/legacy/supervised_user_shared_settings_service_unittest.cc

 // Copyright 2014 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 "chrome/browser/supervised_user/legacy/supervised_user_shared_settings_service.h"
 
 #include <string>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 69 matching lines @@
 
 class SupervisedUserSharedSettingsServiceTest : public ::testing::Test {
  protected:
   typedef base::CallbackList<void(const std::string&, const std::string&)>
       CallbackList;
 
   SupervisedUserSharedSettingsServiceTest()
       : settings_service_(profile_.GetPrefs()) {}
   ~SupervisedUserSharedSettingsServiceTest() override {}
 
-  void StartSyncing(const syncer::SyncDataList& initial_sync_data) {
+  SyncMergeResult StartSyncing(const syncer::SyncDataList& initial_sync_data) {
     sync_processor_.reset(new syncer::FakeSyncChangeProcessor);
     scoped_ptr<syncer::SyncErrorFactory> error_handler(
         new MockSyncErrorFactory(SUPERVISED_USER_SHARED_SETTINGS));
     SyncMergeResult result = settings_service_.MergeDataAndStartSyncing(
         SUPERVISED_USER_SHARED_SETTINGS, initial_sync_data,
         scoped_ptr<SyncChangeProcessor>(
             new SyncChangeProcessorWrapperForTest(sync_processor_.get())),
         std::move(error_handler));
     EXPECT_FALSE(result.error().IsSet());
+    return result;
   }
 
   const base::DictionaryValue* GetAllSettings() {
     return profile_.GetPrefs()->GetDictionary(
         prefs::kSupervisedUserSharedSettings);
   }
 
   void VerifySyncChangesAndClear() {
     SyncChangeList& changes = sync_processor_->changes();
     for (const SyncChange& sync_change : changes) {
@@ skipping 115 matching lines @@
   EXPECT_EQ(ToJson(&name),
             ToJson(settings_service_.GetValue(kIdA, "name")));
   EXPECT_EQ(ToJson(&age), ToJson(settings_service_.GetValue(kIdA, "age")));
   EXPECT_EQ(ToJson(&bar), ToJson(settings_service_.GetValue(kIdB, "foo")));
   EXPECT_EQ(ToJson(&blurp), ToJson(settings_service_.GetValue(kIdC, "baz")));
   EXPECT_FALSE(settings_service_.GetValue(kIdA, "foo"));
   EXPECT_FALSE(settings_service_.GetValue(kIdB, "name"));
   EXPECT_FALSE(settings_service_.GetValue(kIdC, "name"));
 }
 
+TEST_F(SupervisedUserSharedSettingsServiceTest, MergeResult) {

[Bernhard Bauer, 2016/01/05 14:10:54]

Can you just merge this into the Merge test (heh)?

[Deepak, 2016/01/06 05:26:30]

Done.

+  // Set initial values, then stop syncing so we can restart.
+  SyncMergeResult result = StartSyncing(SyncDataList());
+  EXPECT_EQ(0u, sync_processor_->changes().size());
+  EXPECT_EQ(0u, changed_settings_.size());
+  EXPECT_EQ(0, result.num_items_added());
+  EXPECT_EQ(0, result.num_items_modified());

[Bernhard Bauer, 2016/01/05 14:10:54]

Also verify the number of deleted items, just for completeness?

[Deepak, 2016/01/06 05:26:30]

Done.

+
+  const char kIdA[] = "aaaaaa";
+  const char kIdB[] = "bbbbbb";
+  const char kIdC[] = "cccccc";
+
+  FundamentalValue age(8);
+  StringValue bar("bar");
+  settings_service_.SetValue(kIdA, "name", StringValue("Jack"));
+  settings_service_.SetValue(kIdA, "age", age);
+  settings_service_.SetValue(kIdB, "foo", bar);
+
+  settings_service_.StopSyncing(SUPERVISED_USER_SHARED_SETTINGS);
+
+  StringValue name("Jill");
+  StringValue blurp("blurp");
+  SyncDataList sync_data;
+  sync_data.push_back(
+      SupervisedUserSharedSettingsService::CreateSyncDataForSetting(
+          kIdA, "name", name, true));
+  sync_data.push_back(
+      SupervisedUserSharedSettingsService::CreateSyncDataForSetting(
+          kIdC, "baz", blurp, true));
+  sync_data.push_back(

[Bernhard Bauer, 2016/01/05 14:10:54]

I don't think we need to test this, as this shouldn't happen in practice (the ID
should be unique for server-side data).

[Deepak, 2016/01/06 05:26:30]

Done.

+      SupervisedUserSharedSettingsService::CreateSyncDataForSetting(
+          kIdC, "baz1", blurp, true));
+
+  result = StartSyncing(sync_data);
+  EXPECT_EQ(2u, sync_processor_->changes().size());
+  VerifySyncChangesAndClear();
+  EXPECT_EQ(3u, changed_settings_.size());
+  EXPECT_EQ(2, result.num_items_added());
+  EXPECT_EQ(1, result.num_items_modified());
+}
+
 TEST_F(SupervisedUserSharedSettingsServiceTest, ProcessChanges) {
   StartSyncing(SyncDataList());
 
   const char kIdA[] = "aaaaaa";
   const char kIdB[] = "bbbbbb";
   const char kIdC[] = "cccccc";
 
   FundamentalValue age(8);
   StringValue bar("bar");
   settings_service_.SetValue(kIdA, "name", StringValue("Jack"));
@@ skipping 22 matching lines @@
       settings_service_.GetAllSyncData(SUPERVISED_USER_SHARED_SETTINGS).size());
   EXPECT_EQ(ToJson(&name),
             ToJson(settings_service_.GetValue(kIdA, "name")));
   EXPECT_EQ(ToJson(&age), ToJson(settings_service_.GetValue(kIdA, "age")));
   EXPECT_EQ(ToJson(&bar), ToJson(settings_service_.GetValue(kIdB, "foo")));
   EXPECT_EQ(ToJson(&blurp), ToJson(settings_service_.GetValue(kIdC, "baz")));
   EXPECT_FALSE(settings_service_.GetValue(kIdA, "foo"));
   EXPECT_FALSE(settings_service_.GetValue(kIdB, "name"));
   EXPECT_FALSE(settings_service_.GetValue(kIdC, "name"));
 }