Do not attempt nested PropertyHandler resolution for argument conversion

Includes fix for return type declaration in PropertyAccessor subclasses.

See gh-36024

spring-beans/src/main/java/org/springframework/beans/AbstractNestablePropertyAccessor.java

@@ -485,6 +485,9 @@ public abstract class AbstractNestablePropertyAccessor extends AbstractPropertyA
 
 	@Override
 	public @Nullable Class<?> getPropertyType(String propertyName) throws BeansException {
+		if (this.wrappedObject == null) {
+			return null;
+		}
 		try {
 			PropertyHandler ph = getPropertyHandler(propertyName);
 			if (ph != null) {

spring-beans/src/main/java/org/springframework/beans/BeanWrapperImpl.java

@@ -189,7 +189,7 @@ public class BeanWrapperImpl extends AbstractNestablePropertyAccessor implements
 	}
 
 	@Override
-	protected @Nullable BeanPropertyHandler getLocalPropertyHandler(String propertyName) {
+	protected @Nullable PropertyHandler getLocalPropertyHandler(String propertyName) {
 		PropertyDescriptor pd = getCachedIntrospectionResults().getPropertyDescriptor(propertyName);
 		return (pd != null ? new BeanPropertyHandler((GenericTypeAwarePropertyDescriptor) pd) : null);
 	}

spring-beans/src/main/java/org/springframework/beans/DirectFieldAccessor.java

@@ -73,7 +73,7 @@ public class DirectFieldAccessor extends AbstractNestablePropertyAccessor {
 
 
 	@Override
-	protected @Nullable FieldPropertyHandler getLocalPropertyHandler(String propertyName) {
+	protected @Nullable PropertyHandler getLocalPropertyHandler(String propertyName) {
 		FieldPropertyHandler propertyHandler = this.fieldMap.get(propertyName);
 		if (propertyHandler == null) {
 			Field field = ReflectionUtils.findField(getWrappedClass(), propertyName);