1968256926
When PDP connects in GSM network, the TCP buffer window size is set to max 8760. If the phone swicthes to UMTS, the TCP buffer size is not updated to UMTS, i.e. GPRS buffer size is still used with limited data transfer spead as a result. This fix makes sure the TCP buffer size is updated when switching network type. Change-Id: Iaa527c84f56cae108f4c7276bbed10552faaff6c