RESTRICT AUTOMERGE Fix make Bluetooth discoverable without additional permission

- Only enable device can be discoverable when the user launch
  "Connected Devices settings" through settings and systemui

Bug: 194695497
Test: make -j42 RunSettingsRoboTests and use test apk to manually test
to verify the device is not discoversable when open "Connected settings"
through test apk.

Change-Id: Ia04ab759b737acf30b782f5c5831dd59f25fb257
(cherry picked from commit d3abbb9821)

tests/robotests/src/com/android/settings/connecteddevice/DiscoverableFooterPreferenceControllerTest.java

@@ -18,6 +18,7 @@ package com.android.settings.connecteddevice;
 import static com.google.common.truth.Truth.assertThat;
 
 import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
@@ -116,14 +117,17 @@ public class DiscoverableFooterPreferenceControllerTest {
     }
 
     @Test
-    public void onResume() {
+    public void onResume_setAlwaysDiscoverableAsTrue_shouldRegisterBluetoothChanged() {
+        mDiscoverableFooterPreferenceController.setAlwaysDiscoverable(true);
         mDiscoverableFooterPreferenceController.onResume();
+
         assertThat(getRegisteredBroadcastReceivers()).contains(mBluetoothChangedReceiver);
         verify(mAlwaysDiscoverable).start();
     }
 
     @Test
-    public void onPause() {
+    public void onPause_setAlwaysDiscoverableAsTrue_shouldUnregisterBluetoothChanged() {
+        mDiscoverableFooterPreferenceController.setAlwaysDiscoverable(true);
         mDiscoverableFooterPreferenceController.onResume();
         mDiscoverableFooterPreferenceController.onPause();
 
@@ -131,6 +135,25 @@ public class DiscoverableFooterPreferenceControllerTest {
         verify(mAlwaysDiscoverable).stop();
     }
 
+    @Test
+    public void onResume_setAlwaysDiscoverableAsFalse_shouldNotRegisterBluetoothChanged() {
+        mDiscoverableFooterPreferenceController.setAlwaysDiscoverable(false);
+        mDiscoverableFooterPreferenceController.onResume();
+
+        assertThat(getRegisteredBroadcastReceivers()).contains(mBluetoothChangedReceiver);
+        verify(mAlwaysDiscoverable, never()).start();
+    }
+
+    @Test
+    public void onPause_setAlwaysDiscoverableAsFalse_shouldNotUnregisterBluetoothChanged() {
+        mDiscoverableFooterPreferenceController.setAlwaysDiscoverable(false);
+        mDiscoverableFooterPreferenceController.onResume();
+        mDiscoverableFooterPreferenceController.onPause();
+
+        assertThat(getRegisteredBroadcastReceivers()).doesNotContain(mBluetoothChangedReceiver);
+        verify(mAlwaysDiscoverable, never()).stop();
+    }
+
     @Test
     public void onBluetoothStateChanged_bluetoothOn_updateTitle() {
         BluetoothAdapter.getDefaultAdapter().setName(DEVICE_NAME);