resources/src/main/java/org/robolectric/res/android/CppAssetManager.java
static String8 createPathNameLocked(final asset_path ap, final String rootDir) {
    String8 path = new String8(ap.path);
    if (rootDir != null) {
      path.appendPath(rootDir);
    }
    return path;
  }
static String8 createPathNameLocked(final asset_path ap, final String rootDir) {
    String8 path = new String8(ap.path);
    if (rootDir != null) {
      path.appendPath(rootDir);
    }
    return path;
  }
/*
Create a path to a loose asset (asset-base/app/rootDir).