Show security info in saved network list

When an access point linked to a saved network is not found,
security info should be shown in dialog of saved network.
Notes that in Android N this list is created with saved networks
and scan result, and that causes security info is not shown for
access points seen around user, but in Android O only saved
networks are used to create a list. That means security info is
shown for all access points listed in the screen.

Bug: 38102896
Test: make RunSettingsRoboTests

Change-Id: Ia0c5184ae7a1325f2628f4c08e29350c5793a08f
(cherry-pick of a8382c11f58ecbfbc5b8d908b97c53d59cf774fe)

tests/robotests/src/com/android/settings/wifi/WifiConfigControllerTest.java

@@ -16,10 +16,6 @@
 
 package com.android.settings.wifi;
 
-import static com.google.common.truth.Truth.assertThat;
-
-import static org.mockito.Mockito.when;
-
 import android.content.Context;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -40,6 +36,9 @@ import org.mockito.MockitoAnnotations;
 import org.robolectric.RuntimeEnvironment;
 import org.robolectric.annotation.Config;
 
+import static com.google.common.truth.Truth.assertThat;
+import static org.mockito.Mockito.when;
+
 @RunWith(SettingsRobolectricTestRunner.class)
 @Config(manifest = TestConfig.MANIFEST_PATH, sdk = TestConfig.SDK_VERSION,
         shadows = ShadowConnectivityManager.class)
@@ -109,6 +108,7 @@ public class WifiConfigControllerTest {
         when(mAccessPoint.isSaved()).thenReturn(true);
         assertThat(mController.isSubmittable()).isTrue();
     }
+
     @Test
     public void isSubmittable_nullAccessPoint_noException() {
         mController = new TestWifiConfigController(mConfigUiBase, mView, null,
@@ -116,6 +116,13 @@ public class WifiConfigControllerTest {
         mController.isSubmittable();
     }
 
+    @Test
+    public void getSignalString_notReachable_shouldHaveNoSignalString() {
+        when(mAccessPoint.isReachable()).thenReturn(false);
+
+        assertThat(mController.getSignalString()).isNull();
+    }
+
     public class TestWifiConfigController extends WifiConfigController {
 
         public TestWifiConfigController(WifiConfigUiBase parent, View view,