core/src/com/google/inject/internal/Messages.java
static Object convert(Object o) {
    ElementSource source = null;
    if (o instanceof ElementSource) {
      source = (ElementSource) o;
      o = source.getDeclaringSource();
    }
    return convert(o, source);
  }
static Object convert(Object o) {
    ElementSource source = null;
    if (o instanceof ElementSource) {
      source = (ElementSource) o;
      o = source.getDeclaringSource();
    }
    return convert(o, source);
  }
Formats an object in a user friendly way.