[Sync] Make SESSIONS an implicit type

chrome/browser/sync/profile_sync_service_harness.cc

Index: chrome/browser/sync/profile_sync_service_harness.cc
diff --git a/chrome/browser/sync/profile_sync_service_harness.cc b/chrome/browser/sync/profile_sync_service_harness.cc
index 45cd86e1dd9697499135b2d4295cb744e235a19b..2df76c4f74022fe91f463c5d563eb578fbd6a051 100644
--- a/chrome/browser/sync/profile_sync_service_harness.cc
+++ b/chrome/browser/sync/profile_sync_service_harness.cc
@@ -32,6 +32,8 @@
 
 using syncer::sessions::SyncSessionSnapshot;
 
+namespace {
+
 // TODO(rsimha): Remove the following lines once crbug.com/91863 is fixed.
 // The amount of time for which we wait for a live sync operation to complete.
 static const int kLiveSyncOperationTimeoutMs = 45000;
@@ -39,6 +41,20 @@ static const int kLiveSyncOperationTimeoutMs = 45000;
 // The amount of time we wait for test cases that verify exponential backoff.
 static const int kExponentialBackoffVerificationTimeoutMs = 60000;
 
+syncer::ModelTypeSet GetUserVisibleTypes() {
+  syncer::ModelTypeSet user_visible_types(syncer::UserTypes());
+  user_visible_types.Remove(syncer::APP_NOTIFICATIONS);
+  user_visible_types.Remove(syncer::APP_SETTINGS);
+  user_visible_types.Remove(syncer::AUTOFILL_PROFILE);
+  user_visible_types.Remove(syncer::EXTENSION_SETTINGS);
+  user_visible_types.Remove(syncer::SEARCH_ENGINES);
+  user_visible_types.Remove(syncer::SESSIONS);
+  user_visible_types.Remove(syncer::HISTORY_DELETE_DIRECTIVES);
+  return user_visible_types;
+}
+
+}
+
 // Simple class to implement a timeout using PostDelayedTask.  If it is not
 // aborted before picked up by a message queue, then it asserts with the message
 // provided.  This class is not thread safe.
@@ -931,7 +947,6 @@ bool ProfileSyncServiceHarness::DisableSyncForDatatype(
   DVLOG(1) << GetClientInfoString(
       "DisableSyncForDatatype("
       + std::string(syncer::ModelTypeToString(datatype)) + ")");
-
   if (service() == NULL) {
     LOG(ERROR) << "DisableSyncForDatatype(): service() is null.";
     return false;
@@ -945,7 +960,9 @@ bool ProfileSyncServiceHarness::DisableSyncForDatatype(
     return true;
   }
 
+  synced_datatypes.RetainAll(GetUserVisibleTypes());
   synced_datatypes.Remove(datatype);
+
   service()->OnUserChoseDatatypes(false, synced_datatypes);
   if (AwaitFullSyncCompletion("Datatype reconfiguration.")) {
     DVLOG(1) << "DisableSyncForDatatype(): Disabled sync for datatype "