[USS] Show USS counters in Types tab

components/sync/engine_impl/model_type_worker_unittest.cc

Index: components/sync/engine_impl/model_type_worker_unittest.cc
diff --git a/components/sync/engine_impl/model_type_worker_unittest.cc b/components/sync/engine_impl/model_type_worker_unittest.cc
index 47b5385fd90eae1c9006e2183e4f67db870dc70d..63c69641dfc1d6436517d718a7d120a0b40cf018 100644
--- a/components/sync/engine_impl/model_type_worker_unittest.cc
+++ b/components/sync/engine_impl/model_type_worker_unittest.cc
@@ -14,6 +14,7 @@
 #include "components/sync/base/fake_encryptor.h"
 #include "components/sync/engine/model_type_processor.h"
 #include "components/sync/engine_impl/commit_contribution.h"
+#include "components/sync/engine_impl/cycle/non_blocking_type_debug_info_emitter.h"
 #include "components/sync/engine_impl/cycle/status_controller.h"
 #include "components/sync/syncable/syncable_util.h"
 #include "components/sync/test/engine/mock_model_type_processor.h"
@@ -131,7 +132,8 @@ class ModelTypeWorkerTest : public ::testing::Test {
         update_encryption_filter_index_(0),
         mock_type_processor_(nullptr),
         mock_server_(kModelType),
-        is_processor_disconnected_(false) {}
+        is_processor_disconnected_(false),
+        preferences_emitter_(kModelType, &type_observers_) {}
 
   ~ModelTypeWorkerTest() override {}
 
@@ -189,9 +191,9 @@ class ModelTypeWorkerTest : public ::testing::Test {
     }
 
     // TODO(maxbogue): crbug.com/529498: Inject pending updates somehow.
-    worker_.reset(
-        new ModelTypeWorker(kModelType, state, std::move(cryptographer_copy),
-                            &mock_nudge_handler_, std::move(processor)));
+    worker_.reset(new ModelTypeWorker(

[pavely, 2016/10/19 18:18:59]

The purpose of the changes in this file is to just make existing tests work.
Meanwhile model_type_worker.cc has some logic changes, there are some counters
updated and some events fired under some conditions. It would be useful to add
tests here to ensure that the counters are updated correctly and events fired
under correct conditions.

[Gang Wu, 2016/10/20 21:35:36]

Done.

+        kModelType, &preferences_emitter_, state, std::move(cryptographer_copy),
+        &mock_nudge_handler_, std::move(processor)));
   }
 
   // Introduce a new key that the local cryptographer can't decrypt.
@@ -456,6 +458,10 @@ class ModelTypeWorkerTest : public ::testing::Test {
   MockNudgeHandler mock_nudge_handler_;
 
   bool is_processor_disconnected_;
+
+  base::ObserverList<TypeDebugInfoObserver> type_observers_;
+
+  NonBlockingTypeDebugInfoEmitter preferences_emitter_;
 };
 
 // Requests a commit and verifies the messages sent to the client and server as