[sync] Remove unused client factory override for tests

It's dead code without plans to be adopted in the future.

Change-Id: I82d727c166601d10498935d89bd31d664b47a9b0
Bug: None
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2959876
Commit-Queue: Mikel Astiz <mastiz@chromium.org>
Commit-Queue: Victor Vianna <victorvianna@google.com>
Auto-Submit: Mikel Astiz <mastiz@chromium.org>
Reviewed-by: Victor Vianna <victorvianna@google.com>
Cr-Commit-Position: refs/heads/master@{#892531}
diff --git a/chrome/browser/sync/sync_service_factory.cc b/chrome/browser/sync/sync_service_factory.cc
index 546b699..aa731d5 100644
--- a/chrome/browser/sync/sync_service_factory.cc
+++ b/chrome/browser/sync/sync_service_factory.cc
@@ -190,12 +190,8 @@
 
   Profile* profile = Profile::FromBrowserContext(context);
 
-  std::unique_ptr<browser_sync::ChromeSyncClient> sync_client =
-      client_factory_
-          ? client_factory_->Run(profile)
-          : std::make_unique<browser_sync::ChromeSyncClient>(profile);
-
-  init_params.sync_client = std::move(sync_client);
+  init_params.sync_client =
+      std::make_unique<browser_sync::ChromeSyncClient>(profile);
   init_params.network_time_update_callback =
       base::BindRepeating(&UpdateNetworkTime);
   init_params.url_loader_factory = profile->GetDefaultStoragePartition()
@@ -323,13 +319,3 @@
   }
   return sync_services;
 }
-
-// static
-void SyncServiceFactory::SetSyncClientFactoryForTest(
-    SyncClientFactory* client_factory) {
-  client_factory_ = client_factory;
-}
-
-// static
-SyncServiceFactory::SyncClientFactory* SyncServiceFactory::client_factory_ =
-    nullptr;
diff --git a/chrome/browser/sync/sync_service_factory.h b/chrome/browser/sync/sync_service_factory.h
index 16b668c..5a873fb 100644
--- a/chrome/browser/sync/sync_service_factory.h
+++ b/chrome/browser/sync/sync_service_factory.h
@@ -18,10 +18,6 @@
 struct DefaultSingletonTraits;
 }  // namespace base
 
-namespace browser_sync {
-class ChromeSyncClient;
-}  // namespace browser_sync
-
 namespace syncer {
 class SyncServiceImpl;
 class SyncService;
@@ -29,10 +25,6 @@
 
 class SyncServiceFactory : public BrowserContextKeyedServiceFactory {
  public:
-  using SyncClientFactory =
-      base::RepeatingCallback<std::unique_ptr<browser_sync::ChromeSyncClient>(
-          Profile*)>;
-
   // Returns the SyncService for the given profile.
   static syncer::SyncService* GetForProfile(Profile* profile);
   // Returns the SyncServiceImpl for the given profile. DO NOT USE unless
@@ -51,9 +43,6 @@
 
   static SyncServiceFactory* GetInstance();
 
-  // Overrides how the SyncClient is created for testing purposes.
-  static void SetSyncClientFactoryForTest(SyncClientFactory* client_factory);
-
   // Iterates over all profiles that have been loaded so far and extract their
   // SyncService if present. Returned pointers are guaranteed to be not null.
   static std::vector<const syncer::SyncService*> GetAllSyncServices();
@@ -70,10 +59,6 @@
   content::BrowserContext* GetBrowserContextToUse(
       content::BrowserContext* context) const override;
 
-  // A factory function for overriding the way the SyncClient is created.
-  // This is a raw pointer so it can be statically initialized.
-  static SyncClientFactory* client_factory_;
-
   DISALLOW_COPY_AND_ASSIGN(SyncServiceFactory);
 };