Update preference screen title.

- Add missing title to preference screen xml so that they will be used to
set the activity title when the fragment is launched.
- Also updated some incorrect preference screen titles.
- Overrides getTitle() in preference fragments that do not use the
preference screen xml.

Bug: 64564191
Test: blaze-bin/screenshots/android/i18nscreenshots/i18nscreenshots
Change-Id: Id72d5ddf18f0962bc484de8bbd847a2e55d6371e

src/com/android/settings/applications/assist/DefaultVoiceInputPicker.java

@@ -24,6 +24,7 @@ import android.text.TextUtils;
 
 import com.android.internal.app.AssistUtils;
 import com.android.internal.logging.nano.MetricsProto;
+import com.android.settings.R;
 import com.android.settings.applications.defaultapps.DefaultAppInfo;
 import com.android.settings.applications.defaultapps.DefaultAppPickerFragment;
 import com.android.settingslib.wrapper.PackageManagerWrapper;
@@ -54,6 +55,11 @@ public class DefaultVoiceInputPicker extends DefaultAppPickerFragment {
         }
     }
 
+    @Override
+    protected int getPreferenceScreenResId() {
+        return R.xml.default_voice_settings;
+    }
+
     @Override
     protected List<VoiceInputDefaultAppInfo> getCandidates() {
         final List<VoiceInputDefaultAppInfo> candidates = new ArrayList<>();