Small callback optimization and unification

src/windows-emulator/process_context.cpp

@@ -201,7 +201,7 @@ handle process_context::create_thread(memory_manager& memory, const uint64_t sta
                                       const uint64_t stack_size)
 {
     emulator_thread t{memory, *this, start_address, argument, stack_size, ++this->spawned_thread_count};
-    auto h = this->threads.store(std::move(t));
-    on_create_thread(h, *this->threads.get(h));
+    auto [h, thr] = this->threads.store_and_get(std::move(t));
+    this->callbacks_->on_create_thread(h, *thr);
     return h;
 }