shadows/framework/src/main/java/org/robolectric/shadows/ShadowPackageManager.java
public void addPackageNoDefaults(PackageInfo packageInfo) {
    PackageStats packageStats = new PackageStats(packageInfo.packageName);
    addPackage(packageInfo, packageStats);
  }
public void addPackageNoDefaults(PackageInfo packageInfo) {
    PackageStats packageStats = new PackageStats(packageInfo.packageName);
    addPackage(packageInfo, packageStats);
  }
Adds a package to the {@link PackageManager}, but doesn't set any default values on it.

Right now it will not set {@link ApplicationInfo#FLAG_INSTALLED} flag on its application, so
if not set explicitly, it will be treated as not installed.