Fix crash when primary user select app installed by secondary user.

- PackageManager.getPackageInfo() can return null. When trying to check
the app permission info, check for null package info and only process
the permission info when package info is available.
- Update usage of PackageManager.MATCH_UNINSTALLED_PACKAGES to
PackageManager.MATCH_ANY_USER, as the implementation for querying
packages for other users have been changed.
- Add PackageManager APIs used by AppStateAppOpsBridge to
IPackageManagerWrapper for test purpose.
- Change UserManager.get() to Context.getSystemService() to fix test
failure.

Change-Id: I52de924618aa252ffaae02b8f06ebe5b1d0def61
Fix: 37409266
Test: make RunSettingsRoboTests

src/com/android/settings/applications/AppCounter.java

@@ -32,7 +32,7 @@ public abstract class AppCounter extends AsyncTask<Void, Void, Integer> {
 
     public AppCounter(Context context, PackageManagerWrapper packageManager) {
         mPm = packageManager;
-        mUm = UserManager.get(context);
+        mUm = (UserManager) context.getSystemService(Context.USER_SERVICE);
     }
 
     @Override