shadows/framework/src/main/java/org/robolectric/android/XmlResourceParserImpl.java
public String qualify(String value) {
    if (value == null) return null;
    if (AttributeResource.isResourceReference(value)) {
      return "@" + ResName.qualifyResourceName(value.trim().substring(1).replace("+", ""), packageName, "attr");
    } else if (AttributeResource.isStyleReference(value)) {
      return "?" + ResName.qualifyResourceName(value.trim().substring(1), packageName, "attr");
    } else {
      return StringResources.processStringResources(value);
    }
  }
public String qualify(String value) {
    if (value == null) return null;
    if (AttributeResource.isResourceReference(value)) {
      return "@" + ResName.qualifyResourceName(value.trim().substring(1).replace("+", ""), packageName, "attr");
    } else if (AttributeResource.isStyleReference(value)) {
      return "?" + ResName.qualifyResourceName(value.trim().substring(1), packageName, "attr");
    } else {
      return StringResources.processStringResources(value);
    }
  }
for testing only...