[Sync] Add support for proxy types

sync/test/engine/mock_connection_manager.cc

Index: sync/test/engine/mock_connection_manager.cc
diff --git a/sync/test/engine/mock_connection_manager.cc b/sync/test/engine/mock_connection_manager.cc
index afdd62db867ed1788768884405390fd286cccd43..cc0c1cb3770471ef4a55050825289974317457eb 100644
--- a/sync/test/engine/mock_connection_manager.cc
+++ b/sync/test/engine/mock_connection_manager.cc
@@ -405,8 +405,10 @@ void MockConnectionManager::ProcessGetUpdates(
 
   // Verify that the GetUpdates filter sent by the Syncer matches the test
   // expectation.
-  for (int i = FIRST_REAL_MODEL_TYPE; i < MODEL_TYPE_COUNT; ++i) {
-    ModelType model_type = ModelTypeFromInt(i);
+  ModelTypeSet protocol_types = ProtocolTypes();
+  for (ModelTypeSet::Iterator iter = protocol_types.First(); iter.Good();
+       iter.Inc()) {
+    ModelType model_type = iter.Get();
     sync_pb::DataTypeProgressMarker const* progress_marker =
         GetProgressMarkerForType(gu.from_progress_marker(), model_type);
     EXPECT_EQ(expected_filter_.Has(model_type), (progress_marker != NULL))