add Gservices settings for adaptive heartbeat parameters and wifi heartbeat interval.

        public static final String GTALK_SERVICE_NOSYNC_HEARTBEAT_INTERVAL_MS =

                "gtalk_nosync_heartbeat_ping_interval_ms";

        /**

         * The maximum heartbeat interval used while on the WIFI network. 

         */

        public static final String GTALK_SERVICE_WIFI_MAX_HEARTBEAT_INTERVAL_MS =

                "gtalk_wifi_max_heartbeat_ping_interval_ms";

        /**

         * The minimum interval for how frequently we send heartbeat pings to the GTalk server.

         */

        public static final String GTALK_SERVICE_MIN_HEARTBEAT_INTERVAL_MS =

                "gtalk_min_heartbeat_ping_interval_ms";

        /**

         * The scale down factor used by adaptive heartbeat logic (to scale down the heartbeat

         * interval) when the previous interval fails to get a response from the server.

         */

        public static final String GTALK_SERVICE_ADAPTIVE_HEARTBEAT_SCALER =

                "gtalk_adaptive_heartbeat_scaler";

        /**

         * The trigger for adaptively scaling down the heartbeat interval. This is the number of

         * consecutive times we failed to get a server response for sending the heartbeat ping.

         */

        public static final String GTALK_SERVICE_ADAPTIVE_HEARTBEAT_TRIGGER =

                "gtalk_adaptive_heartbeat_trigger";

        /**

         * How long we wait to receive a heartbeat ping acknowledgement (or another packet)

         * from the GTalk server, before deeming the connection dead.