void addDeferredType(TypeElement type, String missingType) {
    // We save the name of the type containing the problem, rather than its TypeElement, because it
    // is not guaranteed that it will be represented by the same TypeElement on the next round. We
    // save the name of the missing type for better diagnostics. (It may be empty.)
    deferredTypeNames.put(type.getQualifiedName().toString(), missingType);
  }
Returns the annotations (in string form) that should be applied to the property's method
implementation.
value/src/main/java/com/google/auto/value/processor/AutoValueishProcessor.java