[sync] skeleton implementation of AutocompleteSyncBridge

components/sync/driver/model_type_controller.cc

Index: components/sync/driver/model_type_controller.cc
diff --git a/components/sync/driver/model_type_controller.cc b/components/sync/driver/model_type_controller.cc
index 313c8c4d5b3ba5a97f6ce1fca7230ed79ba061df..0cb29e00bbd2f07a5f2112587815dc5d0638da39 100644
--- a/components/sync/driver/model_type_controller.cc
+++ b/components/sync/driver/model_type_controller.cc
@@ -26,6 +26,36 @@
 
 namespace syncer {
 
+namespace {

[maxbogue, 2016/11/18 22:22:36]

line below

[Patrick Noland, 2016/11/22 18:51:05]

Done.

+static void CallOnSyncStartingHelper(

[maxbogue, 2016/11/18 22:22:36]

static here and on the other two is actually redundant with the anonymous
namespace:
http://stackoverflow.com/questions/25724787/static-functions-outside-classes

[Patrick Noland, 2016/11/22 18:51:05]

Done.

+    SyncClient* sync_client,
+    ModelType type,
+    std::unique_ptr<DataTypeErrorHandler> error_handler,
+    ModelTypeChangeProcessor::StartCallback callback) {
+  base::WeakPtr<ModelTypeSyncBridge> bridge =
+      sync_client->GetSyncBridgeForModelType(type);
+  bridge->OnSyncStarting(std::move(error_handler), callback);

[pavely, 2016/11/21 22:54:19]

You need to explicitly check if bridge is still valid:
if (bridge)
  bridge->OnSyncStarting(...)

Previously base::Bind & co was doing it for you.

(same in the other two functions)

[Patrick Noland, 2016/11/22 18:51:05]

Done.

+}
+
+static void CallGetAllNodesHelper(
+    SyncClient* sync_client,
+    ModelType type,
+    DataTypeController::AllNodesCallback callback) {
+  base::WeakPtr<ModelTypeSyncBridge> bridge =
+      sync_client->GetSyncBridgeForModelType(type);
+  ModelTypeDebugInfo::GetAllNodes(bridge, callback);
+}
+
+static void CallGetStatusCountersHelper(
+    SyncClient* sync_client,
+    ModelType type,
+    const DataTypeController::StatusCountersCallback& callback) {
+  base::WeakPtr<ModelTypeSyncBridge> bridge =
+      sync_client->GetSyncBridgeForModelType(type);
+  ModelTypeDebugInfo::GetStatusCounters(bridge, callback);
+}
+}  // namespace

[maxbogue, 2016/11/18 22:22:36]

line above

[Patrick Noland, 2016/11/22 18:51:05]

Done.

+
 ModelTypeController::ModelTypeController(
     ModelType type,
     const base::Closure& dump_stack,
@@ -69,26 +99,21 @@ void ModelTypeController::LoadModels(
 
   // Start the type processor on the model thread.
   model_thread_->PostTask(
-      FROM_HERE, base::Bind(&ModelTypeSyncBridge::OnSyncStarting,
-                            sync_client_->GetSyncBridgeForModelType(type()),
+      FROM_HERE, base::Bind(&CallOnSyncStartingHelper, sync_client_, type(),
                             base::Passed(CreateErrorHandler()), callback));
 }
 
 void ModelTypeController::GetAllNodes(const AllNodesCallback& callback) {
-  base::WeakPtr<ModelTypeSyncBridge> bridge =
-      sync_client_->GetSyncBridgeForModelType(type());
-  model_thread_->PostTask(FROM_HERE,
-                          base::Bind(&ModelTypeDebugInfo::GetAllNodes, bridge,
-                                     BindToCurrentThread(callback)));
+  model_thread_->PostTask(
+      FROM_HERE, base::Bind(&CallGetAllNodesHelper, sync_client_, type(),
+                            BindToCurrentThread(callback)));
 }
 
 void ModelTypeController::GetStatusCounters(
     const StatusCountersCallback& callback) {
-  base::WeakPtr<ModelTypeSyncBridge> bridge =
-      sync_client_->GetSyncBridgeForModelType(type());
   model_thread_->PostTask(
       FROM_HERE,
-      base::Bind(&ModelTypeDebugInfo::GetStatusCounters, bridge, callback));
+      base::Bind(&CallGetStatusCountersHelper, sync_client_, type(), callback));

[pavely, 2016/11/21 22:54:19]

Unrelated to your change...
Do we need BindToCurrentThread(callback) here as well?

[Patrick Noland, 2016/11/22 18:51:05]

As far as I can tell, yes. Done.

 }
 
 void ModelTypeController::LoadModelsDone(ConfigureResult result,