Add callback list to PrefModelAssociator after sync data is loaded

components/syncable_prefs/pref_service_syncable_unittest.cc

Index: components/syncable_prefs/pref_service_syncable_unittest.cc
diff --git a/components/syncable_prefs/pref_service_syncable_unittest.cc b/components/syncable_prefs/pref_service_syncable_unittest.cc
index 5aaa09616db396c3a53545ddeb412651e6ea4e59..6e1fcc328119fb7522b5f785ac8053123b1b7106 100644
--- a/components/syncable_prefs/pref_service_syncable_unittest.cc
+++ b/components/syncable_prefs/pref_service_syncable_unittest.cc
@@ -46,6 +46,11 @@ const char kDefaultCharsetPrefName[] = "default_charset";
 const char kNonDefaultCharsetValue[] = "foo";
 const char kDefaultCharsetValue[] = "utf-8";
 
+int kNumCallbacks = 0;
+void CallbackFunc(int* num) {
+  (*num)++;
+}
+
 class TestPrefModelAssociatorClient : public PrefModelAssociatorClient {
  public:
   TestPrefModelAssociatorClient() {}
@@ -121,7 +126,6 @@ class PrefServiceSyncableTest : public testing::Test {
     pref_sync_service_ = reinterpret_cast<PrefModelAssociator*>(
         prefs_.GetSyncableService(syncer::PREFERENCES));
     ASSERT_TRUE(pref_sync_service_);
-    next_pref_remote_sync_node_id_ = 0;
   }
 
   syncer::SyncChange MakeRemoteChange(int64_t id,
@@ -555,6 +559,15 @@ TEST_F(PrefServiceSyncableTest, DeletePreference) {
   EXPECT_TRUE(pref->IsDefaultValue());
 }
 
+TEST_F(PrefServiceSyncableTest, RegisterMergeDataFinishedCallback) {
+  EXPECT_EQ(0, kNumCallbacks);
+  prefs_.RegisterMergeDataFinishedCallback(
+      base::Bind(&CallbackFunc, &kNumCallbacks));

[raymes, 2016/07/14 02:58:51]

can kNumCallbacks be a local variable?

[lshang, 2016/07/14 04:10:24]

Done.

+  EXPECT_EQ(0, kNumCallbacks);
+  InitWithNoSyncData();
+  EXPECT_EQ(1, kNumCallbacks);
+}
+
 }  // namespace
 
 }  // namespace syncable_prefs