Improve multi user settings screen

- Added switch and user delete functionality to details screen.
- Added robo tests.

Screenshots: http://shortn/_S6fbIMhAYO
Bug: 142798722
Test: Run robo tests with this command:
  make -j64 RunSettingsRoboTests ROBOTEST_FILTER="com.android.settings.users.*SettingsTest"
Change-Id: Ied67290e8fed87feb0a60a3f2c40eb91cc57988e

src/com/android/settings/users/AppRestrictionsFragment.java

@@ -97,8 +97,15 @@ public class AppRestrictionsFragment extends SettingsPreferenceFragment implemen
     /** Key for extra passed in from calling fragment to indicate if this is a newly created user */
     public static final String EXTRA_NEW_USER = "new_user";
 
+    /**
+     * Key for extra passed in from calling fragment to indicate if
+     * switch to user should be shown
+     */
+    public static final String EXTRA_SHOW_SWITCH_USER = "enable_switch";
+
     private boolean mFirstTime = true;
     private boolean mNewUser;
+    protected boolean mShowSwitchUser;
     private boolean mAppListChanged;
     protected boolean mRestrictedProfile;
 
@@ -219,6 +226,7 @@ public class AppRestrictionsFragment extends SettingsPreferenceFragment implemen
                     mUser = new UserHandle(args.getInt(EXTRA_USER_ID));
                 }
                 mNewUser = args.getBoolean(EXTRA_NEW_USER, false);
+                mShowSwitchUser = args.getBoolean(EXTRA_SHOW_SWITCH_USER, false);
             }
         }