Add wakeup alarm anomaly detector

Wakeup alarm count frequent is calculated by a / b, where
1. a: the total wakeup alarm count since the last full charge
2. b: total time running since last full charge
(include sleeping time)

This cl also has the following changes:
1. Move bunch of methods to BatteryUtils
2. Create type WAKEUP_ALARM
3. Add and update tests

Upcoming cl will make sure we get the threshold from
AnomalyDetectionPolicy

Bug: 36921529
Test: RunSettingsRoboTests
Change-Id: I4f7b85606df68b6057f6c7d3f3be7f9a9a747f1d

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

@@ -27,6 +27,8 @@ import android.util.Log;
 import android.util.SparseLongArray;
 
 import com.android.internal.os.BatterySipper;
+import com.android.internal.os.BatteryStatsHelper;
+import com.android.internal.util.ArrayUtils;
 import com.android.settings.overlay.FeatureFactory;
 
 import java.lang.annotation.Retention;
@@ -213,6 +215,38 @@ public class BatteryUtils {
         return (powerUsageMah / (totalPowerMah - hiddenPowerMah)) * dischargeAmount;
     }
 
+    /**
+     * Calculate the whole running time in the state {@code statsType}
+     *
+     * @param batteryStatsHelper utility class that contains the data
+     * @param statsType state that we want to calculate the time for
+     * @return the running time in millis
+     */
+    public long calculateRunningTimeBasedOnStatsType(BatteryStatsHelper batteryStatsHelper,
+            int statsType) {
+        final long elapsedRealtimeUs = convertMsToUs(SystemClock.elapsedRealtime());
+        // Return the battery time (millisecond) on status mStatsType
+        return convertUsToMs(
+                batteryStatsHelper.getStats().computeBatteryRealtime(elapsedRealtimeUs, statsType));
+
+    }
+
+    /**
+     * Find the package name for a {@link android.os.BatteryStats.Uid}
+     *
+     * @param uid id to get the package name
+     * @return the package name. If there are multiple packages related to
+     * given id, return the first one. Or return null if there are no known
+     * packages with the given id
+     *
+     * @see PackageManager#getPackagesForUid(int)
+     */
+    public String getPackageName(int uid) {
+        final String[] packageNames = mPackageManager.getPackagesForUid(uid);
+
+        return ArrayUtils.isEmpty(packageNames) ? null : packageNames[0];
+    }
+
     private long convertUsToMs(long timeUs) {
         return timeUs / 1000;
     }