Battery usage page latency improvement (1-8)

Save battery slot diff data into database in hourly job. Then read the
saved diff data and only calculate the remaining data. This could speed
up the battery usage loading.

Bug: 261163071
Fix: 261163071
Test: manual
Change-Id: Icd4868ca9326b64b17ddbccdb0311e755dc68026

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

@@ -45,7 +45,6 @@ import com.android.settings.fuelgauge.batterytip.tips.BatteryTip;
 import com.android.settings.overlay.FeatureFactory;
 import com.android.settings.search.BaseSearchIndexProvider;
 import com.android.settingslib.search.SearchIndexable;
-import com.android.settingslib.widget.LayoutPreference;
 
 import java.util.List;
 
@@ -69,8 +68,6 @@ public class PowerUsageSummary extends PowerUsageBase implements
     @VisibleForTesting
     BatteryUtils mBatteryUtils;
     @VisibleForTesting
-    LayoutPreference mBatteryLayoutPref;
-    @VisibleForTesting
     BatteryInfo mBatteryInfo;
 
     @VisibleForTesting
@@ -208,11 +205,6 @@ public class PowerUsageSummary extends PowerUsageBase implements
         return R.string.help_url_battery;
     }
 
-    @Override
-    protected boolean isBatteryHistoryNeeded() {
-        return false;
-    }
-
     protected void refreshUi(@BatteryUpdateType int refreshType) {
         final Context context = getContext();
         if (context == null) {
@@ -239,11 +231,6 @@ public class PowerUsageSummary extends PowerUsageBase implements
         restartLoader(LoaderIndex.BATTERY_TIP_LOADER, Bundle.EMPTY, mBatteryTipsCallbacks);
     }
 
-    @VisibleForTesting
-    void setBatteryLayoutPreference(LayoutPreference layoutPreference) {
-        mBatteryLayoutPref = layoutPreference;
-    }
-
     @VisibleForTesting
     void initFeatureProvider() {
         final Context context = getContext();