Show "no vpns added" for empty vpn screen

Removed the left-alignment on restricted empty views which was
inherited from Bluetooth settings but inconsistent with normal
settings fragments.

Bug: 22685111
Change-Id: I3a36c47d523392b8925031d4cac2ab3ef681e360

res/layout/preference_list_fragment.xml

@@ -67,10 +67,11 @@
     </FrameLayout>
 
     <TextView android:id="@android:id/empty"
-        android:layout_width="match_parent"
+        android:layout_width="wrap_content"
         android:layout_height="match_parent"
         android:padding="@*android:dimen/preference_fragment_padding_side"
-        android:gravity="center"
+        android:layout_gravity="center"
+        android:gravity="center_vertical"
         android:visibility="gone" />
 
     <include layout="@layout/admin_support_details_empty_view" />

res/values/strings.xml

@@ -5195,6 +5195,8 @@
     <string name="vpn_menu_delete">Delete profile</string>
     <!-- Menu item to select always-on VPN profile. [CHAR LIMIT=40] -->
     <string name="vpn_menu_lockdown">Always-on VPN</string>
+    <!-- Placeholder when VPN settings is open but no VPNs have been created. [CHAR LIMIT=100] -->
+    <string name="vpn_no_vpns_added">No VPNs added.</string>
 
     <!-- Summary describing the always-on VPN feature. [CHAR LIMIT=NONE] -->
     <string name="vpn_lockdown_summary">Select a VPN profile to always remain connected to. Network traffic will only be allowed when connected to this VPN.</string>

src/com/android/settings/RestrictedSettingsFragment.java

@@ -209,7 +209,6 @@ public abstract class RestrictedSettingsFragment extends SettingsPreferenceFragm
 
     protected TextView initEmptyTextView() {
         TextView emptyView = (TextView) getActivity().findViewById(android.R.id.empty);
-        emptyView.setGravity(Gravity.START | Gravity.CENTER_VERTICAL);
         return emptyView;
     }
 

src/com/android/settings/vpn2/VpnSettings.java

@@ -111,20 +111,15 @@ public class VpnSettings extends RestrictedSettingsFragment implements
     }
 
     @Override
-    public void onCreate(Bundle savedState) {
-        super.onCreate(savedState);
+    public void onActivityCreated(Bundle savedInstanceState) {
+        super.onActivityCreated(savedInstanceState);
 
         mUserManager = (UserManager) getSystemService(Context.USER_SERVICE);
-        if (isUiRestricted()) {
-            mUnavailable = true;
-            setPreferenceScreen(new PreferenceScreen(getPrefContext(), null));
-            setHasOptionsMenu(false);
-            return;
-        }
-
         mConnectivityManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
 
-        setHasOptionsMenu(true);
+        mUnavailable = isUiRestricted();
+        setHasOptionsMenu(!mUnavailable);
+
         addPreferencesFromResource(R.xml.vpn_settings2);
     }
 
@@ -186,6 +181,8 @@ public class VpnSettings extends RestrictedSettingsFragment implements
             }
             getPreferenceScreen().removeAll();
             return;
+        } else {
+            getEmptyTextView().setText(R.string.vpn_no_vpns_added);
         }
 
         final boolean pickLockdown = getActivity()