[Sync] Sanity test for UserEvents.

chrome/browser/sync/test/integration/migration_test.cc

 // Copyright 2012 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 <memory>
 #include <vector>
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
@@ skipping 94 matching lines @@
 
     // Autofill wallet will be unready during this test, so we should not
     // request that it be migrated.
     preferred_data_types.Remove(syncer::AUTOFILL_WALLET_DATA);
     preferred_data_types.Remove(syncer::AUTOFILL_WALLET_METADATA);
 
     // ARC package will be unready during this test, so we should not request
     // that it be migrated.
     preferred_data_types.Remove(syncer::ARC_PACKAGE);
 
+    // Doesn't make sense to migrate commit only types.
+    preferred_data_types.RemoveAll(syncer::CommitOnlyTypes());
+
     // Make sure all clients have the same preferred data types.
     for (int i = 1; i < num_clients(); ++i) {
       const syncer::ModelTypeSet other_preferred_data_types =
           GetSyncService(i)->GetPreferredDataTypes();
       EXPECT_EQ(other_preferred_data_types, preferred_data_types);
     }
     return preferred_data_types;
   }
 
   // Returns a MigrationList with every enabled data type in its own
@@ skipping 30 matching lines @@
         break;
       default:
         ADD_FAILURE();
     }
   }
 
   // Block until all clients have completed migration for the given
   // types.
   void AwaitMigration(syncer::ModelTypeSet migrate_types) {
     for (int i = 0; i < num_clients(); ++i) {
+      LOG(ERROR) << "SKYM " << syncer::ModelTypeSetToString(migrate_types);

[Patrick Noland, 2017/06/26 19:20:23]

Did you mean to include this? If so, could you make the message a bit for
informative?

[skym, 2017/06/26 19:59:40]

I did not! Whoops. Removed.

       ASSERT_TRUE(
           MigrationWaiter(migrate_types, migration_watchers_[i].get()).Wait());
     }
   }
 
   // Makes sure migration works with the given migration list and
   // trigger method.
   void RunMigrationTest(const MigrationList& migration_list,
                         TriggerMethod trigger_method) {
     // If we have only one client, turn off notifications to avoid the
@@ skipping 253 matching lines @@
     // Do not add optional datatypes.
   }
 
   ~MigrationReconfigureTest() override {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(MigrationReconfigureTest);
 };
 
 }  // namespace