Add Statistics for SupervisedUserSettingService during merging and syncing data.

chrome/browser/supervised_user/legacy/supervised_user_shared_settings_service_unittest.cc

Index: chrome/browser/supervised_user/legacy/supervised_user_shared_settings_service_unittest.cc
diff --git a/chrome/browser/supervised_user/legacy/supervised_user_shared_settings_service_unittest.cc b/chrome/browser/supervised_user/legacy/supervised_user_shared_settings_service_unittest.cc
index e7b0675550bc3431854fd4d9eb927d68564d4b38..cad5e6f7f351dea938f467a49d1d0c5424a9ad41 100644
--- a/chrome/browser/supervised_user/legacy/supervised_user_shared_settings_service_unittest.cc
+++ b/chrome/browser/supervised_user/legacy/supervised_user_shared_settings_service_unittest.cc
@@ -87,7 +87,7 @@ class SupervisedUserSharedSettingsServiceTest : public ::testing::Test {
       : 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));
@@ -97,6 +97,7 @@ class SupervisedUserSharedSettingsServiceTest : public ::testing::Test {
             new SyncChangeProcessorWrapperForTest(sync_processor_.get())),
         std::move(error_handler));
     EXPECT_FALSE(result.error().IsSet());
+    return result;
   }
 
   const base::DictionaryValue* GetAllSettings() {
@@ -232,6 +233,47 @@ TEST_F(SupervisedUserSharedSettingsServiceTest, Merge) {
   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());