[Robustness] protect get battery stats from DeadSystemException

Refine the original workaround patch in the ag/15527095 from NPE to
return default BatteryUsageStats instance as we merged in the
ag/15919139 (align the same solution).

Bug: 195306545
Test: make SettingsRoboTests
Change-Id: Ic03e8296d16ecb8629155f75727e9cde48c303eb

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

@@ -373,8 +373,11 @@ public class BatteryUtils {
             batteryUsageStats = systemService.getBatteryUsageStats(
                     new BatteryUsageStatsQuery.Builder().includeBatteryHistory().build());
         } catch (RuntimeException e) {
-            Log.e(TAG, "getBatteryInfo() from getBatteryUsageStats()", e);
-            return null;
+            Log.e(TAG, "getBatteryInfo() error from getBatteryUsageStats()", e);
+            // Use default BatteryUsageStats.
+            batteryUsageStats =
+                    new BatteryUsageStats.Builder(new String[0], /* includePowerModels */ false)
+                            .build();
         }
 
         final long startTime = System.currentTimeMillis();