Program: 38067
Project: 38067
Buggy source:
@Override public void onCreate(Bundle savedInstanceState){
  super.onCreate(savedInstanceState);
  appContext=getApplicationContext();
  Toolbar toolbar=(Toolbar)findViewById(R.id.toolbar);
  setSupportActionBar(toolbar);
  settings=PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
  if (!settings.contains("String_Node_Str")) {
    if (BuildConfig.FIXED_SCHOOL == null) {
      Intent intent=new Intent(this,SelectSchoolActivity.class);
      startActivity(intent);
      finish();
    }
 else {
      settings.edit().putString("String_Node_Str",BuildConfig.FIXED_SCHOOL).commit();
    }
  }
  if (!isTablet()) {
    vertretungFragment=new VertretungFragment();
    nachrichtenFragment=new NachrichtenFragment();
    addTab("String_Node_Str",vertretungFragment);
    addTab("String_Node_Str",nachrichtenFragment);
    tabs=(PagerSlidingTabStrip)findViewById(R.id.tabs);
    tabs.setViewPager(mViewPager);
    tabs.setOnPageChangeListener(adapter);
  }
 else {
    vertretungFragment=(VertretungFragment)getSupportFragmentManager().findFragmentById(R.id.vertretung_fragment);
    nachrichtenFragment=(NachrichtenFragment)getSupportFragmentManager().findFragmentById(R.id.nachrichten_fragment);
  }
  content=findViewById(R.id.content);
  pBar=(ProgressBar)findViewById(R.id.progressBar);
  showDialogs();
  if (savedInstanceState == null) {
    if (gcmRegistered) {
      new GetVertretungsplanTask().execute();
    }
    created=true;
  }
 else {
    Log.d("String_Node_Str","String_Node_Str");
    vertretungsplan=new Gson().fromJson(savedInstanceState.getString("String_Node_Str"),Vertretungsplan.class);
  }
  FontUtils.setRobotoFont(this,findViewById(android.R.id.content));
}

Fixed version (ground truth):
@Override public void onCreate(Bundle savedInstanceState){
  super.onCreate(savedInstanceState);
  appContext=getApplicationContext();
  Toolbar toolbar=(Toolbar)findViewById(R.id.toolbar);
  setSupportActionBar(toolbar);
  settings=PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
  if (!settings.contains("String_Node_Str")) {
    if (BuildConfig.FIXED_SCHOOL == null) {
      Intent intent=new Intent(this,SelectSchoolActivity.class);
      startActivity(intent);
      finish();
    }
 else {
      settings.edit().putString("String_Node_Str",BuildConfig.FIXED_SCHOOL).commit();
    }
  }
  if (!isTablet()) {
    vertretungFragment=new VertretungFragment();
    nachrichtenFragment=new NachrichtenFragment();
    addTab("String_Node_Str",vertretungFragment);
    addTab("String_Node_Str",nachrichtenFragment);
    tabs=(PagerSlidingTabStrip)findViewById(R.id.tabs);
    tabs.setViewPager(mViewPager);
    tabs.setOnPageChangeListener(adapter);
  }
 else {
    vertretungFragment=(VertretungFragment)getSupportFragmentManager().findFragmentById(R.id.vertretung_fragment);
    nachrichtenFragment=(NachrichtenFragment)getSupportFragmentManager().findFragmentById(R.id.nachrichten_fragment);
  }
  content=findViewById(R.id.content);
  pBar=(ProgressBar)findViewById(R.id.progressBar);
  showDialogs();
  if (savedInstanceState == null) {
    if (gcmRegistered) {
      new GetVertretungsplanTask().execute();
    }
    created=true;
  }
 else {
    Log.d("String_Node_Str","String_Node_Str");
    vertretungsplan=new Gson().fromJson(savedInstanceState.getString("String_Node_Str"),Vertretungsplan.class);
    if (vertretungsplan != null)     setVertretungsplan(vertretungsplan);
  }
  FontUtils.setRobotoFont(this,findViewById(android.R.id.content));
}