Automatic timezone support on non-telephony devices

Adding to the Settings UI in order to simplify timezone on non-telephony devices.

Test: on-device testing, additional unit tests
Change-Id: I58ece9542a7b80823092bd082d4bd8c224b29634
Bug: 253015306

src/com/android/settings/datetime/AutoTimeZonePreferenceController.java

@@ -29,8 +29,10 @@ import android.content.Context;
 
 import androidx.annotation.VisibleForTesting;
 import androidx.preference.Preference;
+import androidx.preference.PreferenceScreen;
 import androidx.preference.SwitchPreference;
 
+import com.android.settings.R;
 import com.android.settings.core.PreferenceControllerMixin;
 import com.android.settingslib.core.AbstractPreferenceController;
 
@@ -99,6 +101,25 @@ public class AutoTimeZonePreferenceController extends AbstractPreferenceControll
         return result;
     }
 
+    @Override
+    public CharSequence getSummary() {
+        // If auto time zone cannot enable telephony fallback and is capable of location, then auto
+        // time zone must use location.
+        if (LocationProviderStatusPreferenceController.hasLocationTimeZoneNoTelephonyFallback(
+                mTimeManager.getTimeZoneCapabilitiesAndConfig().getDetectorStatus())) {
+            return mContext.getResources().getString(R.string.auto_zone_requires_location_summary);
+        }
+        // If the user has a dedicated toggle to control location use, the summary can
+        // be empty because the use of location is explicit.
+        return "";
+    }
+
+    @Override
+    public void displayPreference(PreferenceScreen screen) {
+        super.displayPreference(screen);
+        refreshSummary(screen.findPreference(getPreferenceKey()));
+    }
+
     @VisibleForTesting
     boolean isEnabled() {
         TimeZoneConfiguration config = getTimeZoneCapabilitiesAndConfig().getConfiguration();