Fixed battery chart flickering

- Hide the hourly chart view by default to avoid the calculate the
  space.
- Remove the alpha animation in chart group which causes the flickering
  when open the battery page.

Bug: 378997970
Flag: EXEMPT bugfix
Test: atest BatteryChartPreferenceControllerTest
Change-Id: I1b7e5f74fe63ebcae9f9737b0797d870fd56b134

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

@@ -274,7 +274,6 @@ public class BatteryChartPreferenceController extends AbstractPreferenceControll
         }
         if (mDailyChartView != dailyChartView || mHourlyChartView != hourlyChartView) {
             mHandler.post(() -> setBatteryChartViewInner(dailyChartView, hourlyChartView));
-            animateBatteryChartViewGroup();
         }
         if (mBatteryChartViewGroup != null) {
             final View grandparentView = (View) mBatteryChartViewGroup.getParent();