AK: Add NeverDestroyed<T>, for things that should never be destroyed

This template allows you to define static globals without having them
destroyed on exit.

AK/NeverDestroyed.h

@@ -0,0 +1,36 @@
+#pragma once
+
+#include <AK/Noncopyable.h>
+#include <AK/StdLibExtras.h>
+
+namespace AK {
+
+template<typename T>
+class NeverDestroyed {
+    AK_MAKE_NONCOPYABLE(NeverDestroyed)
+    AK_MAKE_NONMOVABLE(NeverDestroyed)
+public:
+    template<typename... Args>
+    NeverDestroyed(Args... args)
+    {
+        new (storage) T(forward<Args>(args)...);
+    }
+
+    ~NeverDestroyed() = default;
+
+    T* operator->() { return &get(); }
+    const T* operator->() const { return &get(); }
+
+    T& operator*() { return get(); }
+    const T* operator*() const { return get(); }
+
+    T& get() { return reinterpret_cast<T&>(storage); }
+    const T& get() const { return reinterpret_cast<T&>(storage); }
+
+private:
+    alignas(T) u8 storage[sizeof(T)];
+};
+
+}
+
+using AK::NeverDestroyed;