BatteryStatsImpl: Keep less history around for low mem devices.

    private static final int VERSION = 159 + (USE_OLD_HISTORY ? 1000 : 0);

    // Maximum number of items we will record in the history.

    private static final int MAX_HISTORY_ITEMS = 2000;

    private static final int MAX_HISTORY_ITEMS;

    // No, really, THIS is the maximum number of items we will record in the history.

    private static final int MAX_MAX_HISTORY_ITEMS = 3000;

    private static final int MAX_MAX_HISTORY_ITEMS;

    // The maximum number of names wakelocks we will keep track of

    // per uid; once the limit is reached, we batch the remaining wakelocks

    // in to one common name.

    private static final int MAX_WAKELOCKS_PER_UID = 100;

    private static final int MAX_WAKELOCKS_PER_UID;

    static final int MAX_HISTORY_BUFFER; // 256KB

    static final int MAX_MAX_HISTORY_BUFFER; // 320KB

    static {

        if (ActivityManager.isLowRamDeviceStatic()) {

            MAX_HISTORY_ITEMS = 800;

            MAX_MAX_HISTORY_ITEMS = 1200;

            MAX_WAKELOCKS_PER_UID = 40;

            MAX_HISTORY_BUFFER = 96*1024;  // 96KB

            MAX_MAX_HISTORY_BUFFER = 128*1024; // 128KB

        } else {

            MAX_HISTORY_ITEMS = 2000;

            MAX_MAX_HISTORY_ITEMS = 3000;

            MAX_WAKELOCKS_PER_UID = 100;

            MAX_HISTORY_BUFFER = 256*1024;  // 256KB

            MAX_MAX_HISTORY_BUFFER = 320*1024;  // 256KB

        }

    }

    // Number of transmit power states the Wifi controller can be in.

    private static final int NUM_WIFI_TX_LEVELS = 1;

    boolean mRecordingHistory = false;

    int mNumHistoryItems;

    static final int MAX_HISTORY_BUFFER = 256*1024; // 256KB

    static final int MAX_MAX_HISTORY_BUFFER = 320*1024; // 320KB

    final Parcel mHistoryBuffer = Parcel.obtain();

    final HistoryItem mHistoryLastWritten = new HistoryItem();

    final HistoryItem mHistoryLastLastWritten = new HistoryItem();