Use en-dash in the time range instead of a hyphen for different format

Expected format: 00:00–02:00 or (2pm – 4pm)

Screenshots:
https://screenshot.googleplex.com/4RvaovK6RN7kjqo
https://screenshot.googleplex.com/ADZRr2TPuuctFre

Bug: 229264053
Test: make RunSettingsRoboTests
Change-Id: Ifd9bea0ce4525c8b582778e255104e875d365563

src/com/android/settings/fuelgauge/BatteryChartPreferenceController.java

@@ -508,7 +508,9 @@ public class BatteryChartPreferenceController extends AbstractPreferenceControll
             mBatteryHistoryKeys[mTrapezoidIndex * 2], mIs24HourFormat);
         final String toHour = ConvertUtils.utcToLocalTimeHour(mPrefContext,
             mBatteryHistoryKeys[(mTrapezoidIndex + 1) * 2], mIs24HourFormat);
-        return String.format("%s - %s", fromHour, toHour);
+        return mIs24HourFormat
+            ? String.format("%s–%s", fromHour, toHour)
+            : String.format("%s – %s", fromHour, toHour);
     }
 
     @VisibleForTesting