public static void addContents(DexFile file, Constant cst) {
    if (cst instanceof CstAnnotation) {
      addContents(file, ((CstAnnotation) cst).getAnnotation());
    } else if (cst instanceof CstArray) {
      CstArray.List list = ((CstArray) cst).getList();
      int size = list.size();
      for (int i = 0; i < size; i++) {
        addContents(file, list.get(i));
      }
    } else {
      file.internIfAppropriate(cst);
    }
  }
Helper for {@code addContents()} methods, which adds contents for a particular constant,
calling itself recursively should it encounter a {@link CstArray} and calling {@link
#addContents(DexFile, Annotation)} recursively should it encounter a {@link CstAnnotation}.

@param file {@code non-null;} the file to add to
@param cst {@code non-null;} the constant to add contents for
android/android_framework/dex-maker/src/main/java/com/android/dx/dex/file/ValueEncoder.java