LibJS: Skip lazy intrinsic allocation check for objects without them

Most JS::Objects don't have lazily-allocated intrinsic properties,
so let's avoid doing hash lookups by putting a flag on JS::Object that
tells us whether it's present in s_intrinsics.

Takes CPU time spent in those hash lookups from 1-2.5% to nothing on
various JS heavy pages.

Userland/Libraries/LibJS/Runtime/Object.h

@@ -212,6 +212,9 @@ private:
     Object* prototype() { return shape().prototype(); }
     Object const* prototype() const { return shape().prototype(); }
 
+    // True if this object has lazily allocated intrinsic properties.
+    bool m_has_intrinsic_accessors { false };
+
     GCPtr<Shape> m_shape;
     Vector<Value> m_storage;
     IndexedProperties m_indexed_properties;