[core] Introduce Pass<> class and use it for Scheduler

Thus we enforce client to retain the returned `Scheduler` objects.

1 files changed, 4 insertions, 4 deletions

diff --git a/src/mbgl/actor/scheduler.cpp b/src/mbgl/actor/scheduler.cpp
index 0e051d0273..d765cfcf65 100644
--- a/src/mbgl/actor/scheduler.cpp
+++ b/src/mbgl/actor/scheduler.cpp
@@ -27,7 +27,7 @@ Scheduler* Scheduler::GetCurrent() {
 }
 
 // static
-std::shared_ptr<Scheduler> Scheduler::GetBackground() {
+PassRefPtr<Scheduler> Scheduler::GetBackground() {
     static std::weak_ptr<Scheduler> weak;
     static std::mutex mtx;
 
@@ -38,11 +38,11 @@ std::shared_ptr<Scheduler> Scheduler::GetBackground() {
         weak = scheduler = std::make_shared<ThreadPool>();
     }
 
-    return scheduler;
+    return PassRefPtr<Scheduler>(std::move(scheduler));
 }
 
 // static
-std::shared_ptr<Scheduler> Scheduler::GetSequenced() {
+PassRefPtr<Scheduler> Scheduler::GetSequenced() {
     const std::size_t kSchedulersCount = 10;
     static std::vector<std::weak_ptr<Scheduler>> weaks(kSchedulersCount);
     static std::mutex mtx;
@@ -65,7 +65,7 @@ std::shared_ptr<Scheduler> Scheduler::GetSequenced() {
         break;
     }
 
-    return result;
+    return PassRefPtr<Scheduler>(std::move(result));
 }
 
 } //namespace mbgl