Remove duplicate strings.

"Yes" and "no" were redefined many times with no clear benefit, so this
consolidates them into one definition.

Bug: 243843096
Test: Build, install, and open the Settings app
Test: atest SettingsRoboTests
Change-Id: I5f84d09f223efd478461ded93aeac82bf7b128d8

src/com/android/settings/dream/DreamSettings.java

@@ -137,7 +137,7 @@ public class DreamSettings extends DashboardFragment implements OnMainSwitchChan
     @VisibleForTesting
     static CharSequence getSummaryTextFromBackend(DreamBackend backend, Context context) {
         if (!backend.isEnabled()) {
-            return context.getString(R.string.screensaver_settings_summary_off);
+            return context.getString(R.string.off);
         } else {
             return backend.getActiveDreamName();
         }