[Sync] Convert DTCs to be not RefCounted and NonThreadSafe.

components/browser_sync/browser/profile_sync_service.cc

Index: components/browser_sync/browser/profile_sync_service.cc
diff --git a/components/browser_sync/browser/profile_sync_service.cc b/components/browser_sync/browser/profile_sync_service.cc
index 1c9aac928fb0966c440626dd5a23679dfeb8bfb3..180cf4271567ba16ab48fa89b3236efd6d1b3cd6 100644
--- a/components/browser_sync/browser/profile_sync_service.cc
+++ b/components/browser_sync/browser/profile_sync_service.cc
@@ -424,9 +424,10 @@ void ProfileSyncService::UnregisterAuthNotifications() {
 }
 
 void ProfileSyncService::RegisterDataTypeController(
-    sync_driver::DataTypeController* data_type_controller) {
+    std::unique_ptr<sync_driver::DataTypeController> data_type_controller) {
   DCHECK_EQ(data_type_controllers_.count(data_type_controller->type()), 0U);

[skym, 2016/09/02 22:45:28]

Ugh, count(...). What do you think of find?

[maxbogue, 2016/09/03 00:14:51]

Didn't compile for some reason... "error: no matching function for call to
'MakeCheckOpValueString'"

I'm just gonna leave it.

-  data_type_controllers_[data_type_controller->type()] = data_type_controller;
+  data_type_controllers_[data_type_controller->type()] =
+      std::move(data_type_controller);
 }
 
 bool ProfileSyncService::IsDataTypeControllerRunning(