Add metric for managed system update callback.

package com.android.server.devicepolicy;

import android.app.admin.DevicePolicyEventLogger;

import android.app.admin.DevicePolicyManager;

import android.app.admin.StartInstallingUpdateCallback;

import android.content.Context;

import android.os.PowerManager;

import android.os.Process;

import android.os.RemoteException;

import android.stats.devicepolicy.DevicePolicyEnums;

import android.util.Log;

import java.io.File;

    protected void notifyCallbackOnError(int errorCode, String errorMessage) {

        cleanupUpdateFile();

        DevicePolicyEventLogger

                .createEvent(DevicePolicyEnums.INSTALL_SYSTEM_UPDATE_ERROR)

                .setInt(errorCode)

                .write();

        try {

            mCallback.onStartInstallingUpdateError(errorCode, errorMessage);

        } catch (RemoteException e) {