Support 4-arg Whitebox.setInternalState(target, field, value, Class)

[MBoegers]

What

Extends PowerMockWhiteboxToJavaReflection to also handle the 4-arg overload
Whitebox.setInternalState(target, "field", value, Class). The 3-arg form was already
migrated; this overload was left untouched.

Why

The 4th argument is the declaring class to look the field up on, and it matters because
getDeclaredField does not walk the class hierarchy. For an inherited field,
child.getClass().getDeclaredField("name") throws NoSuchFieldException — only
Parent.class.getDeclaredField("name") resolves it. This overload is exactly what test code
uses to reach a field declared on a superclass.

The only semantic difference from the 3-arg path is the receiver of getDeclaredField:

Overload	Generated lookup receiver
3-arg setInternalState(child, "name", v)	child.getClass() (runtime class only)
4-arg setInternalState(child, "name", v, Parent.class)	Parent.class (declaring superclass)

Everything else — setAccessible(true), field.set(target, value), the throws Exception,
the java.lang.reflect.Field import — is identical to the shipped 3-arg path. No cast, no boxing.

Before → After

// before
Whitebox.setInternalState(child, "name", "newValue", Parent.class);

// after
Field nameField = Parent.class.getDeclaredField("name");
nameField.setAccessible(true);
nameField.set(child, "newValue");

Notes

• New MethodMatcher for setInternalState(Object, String, Object, Class); the String 2nd
  param disambiguates it from the setInternalState(Object, Class, Object, Class) sibling overload.
• The 4th Class argument flows straight into a #{any(java.lang.Class)} placeholder, so a
  non-literal Class<?> variable as the 4th arg works too (generates where.getDeclaredField(...)).
• No catalog/YAML change — the recipe is already wired in and displayName/description are unchanged.

Tests

Two new tests in PowerMockWhiteboxToJavaReflectionTest:

• setInternalStateWithWhereClass — inherited field via a literal Parent.class.
• setInternalStateWithWhereClassVariable — a Class<?> variable as the 4th arg.

./gradlew check passes (license, recipe CSV completeness/content validation, full test suite).

[MBoegers]

#1021 is an ongoing refactoring with @steve-aom-elliott to break the recipe for expansion. This is the most pressing missing API.