sandbox/src/main/java/org/robolectric/internal/bytecode/ClassInstrumentor.java
protected void makeMethodPrivate(MethodNode method) {
    method.access = (method.access | Opcodes.ACC_PRIVATE) & ~(Opcodes.ACC_PUBLIC | Opcodes.ACC_PROTECTED);
  }
protected void makeMethodPrivate(MethodNode method) {
    method.access = (method.access | Opcodes.ACC_PRIVATE) & ~(Opcodes.ACC_PUBLIC | Opcodes.ACC_PROTECTED);
  }
Replaces protected and public class modifiers with private.