Add getTitle() for ButtonPreference

Bug: 233038449
Test: make RunSettingsRoboTests ROBOTEST_FILTER=ButtonPreferenceTest
Change-Id: Ie2f24879bce026e5bc3d7fedfcb3a6475ab7d404

packages/SettingsLib/ButtonPreference/src/com/android/settingslib/widget/ButtonPreference.java

@@ -132,6 +132,10 @@ public class ButtonPreference extends Preference {
         }
     }
 
+    @Override public CharSequence getTitle() {
+        return mTitle;
+    }
+
     @Override
     public void setIcon(Drawable icon) {
         mIcon = icon;

packages/SettingsLib/tests/robotests/src/com/android/settingslib/widget/ButtonPreferenceTest.java

@@ -63,6 +63,7 @@ public class ButtonPreferenceTest {
 
         final Button button = mPreference.getButton();
         assertThat(button.getText().toString()).isEqualTo(testTitle);
+        assertThat(mPreference.getTitle().toString()).isEqualTo(testTitle);
     }
 
     @Test