Make some gesture related slices public.

Only PreferenceControllers with isPublicSlice() set to true are exposed
to other apps. Others will be Settings only.

Bug: 141088937
Test: robotests
Change-Id: I0b54e752c5982f13193590db47dc3a84dde5311d

tests/robotests/src/com/android/settings/gestures/TapScreenGesturePreferenceControllerTest.java

@@ -30,7 +30,6 @@ import android.hardware.display.AmbientDisplayConfiguration;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
-import org.mockito.Answers;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 import org.robolectric.RobolectricTestRunner;
@@ -90,4 +89,9 @@ public class TapScreenGesturePreferenceControllerTest {
                 new TapScreenGesturePreferenceController(mContext, KEY_WAKE_LOCK_SCREEN);
         assertThat(controller.isSliceable()).isTrue();
     }
+
+    @Test
+    public void isPublicSlice_returnTrue() {
+        assertThat(mController.isPublicSlice()).isTrue();
+    }
 }