win: fix narrowing warning in tcp_socket
win: fix narrowing warning in tcp_socket

VS2015 reports

d:\src\cr3\src\net\socket\tcp_socket_win.cc(88): warning C4838: conversion from 'int' to 'ULONG' requires a narrowing conversion

R=mattm@chromium.org
BUG=440500

Review URL: https://codereview.chromium.org/1080203002

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#325067}

Chilledheart/chromium,ltilve/chromium,Pluto-tv/chromium-crosswalk,chuan9/chromium-crosswalk,axinging/chromium-crosswalk,Fireblend/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,chuan9/chromium-crosswalk,Just-D/chromium-1,axinging/chromium-crosswalk,axinging/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,Chilledheart/chromium,hgl888/chromium-crosswalk,Pluto-tv/chromium-crosswalk,axinging/chromium-crosswalk,ltilve/chromium,hgl888/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,Pluto-tv/chromium-crosswalk,hgl888/chromium-crosswalk,axinging/chromium-crosswalk,hgl888/chromium-crosswalk,ltilve/chromium,hgl888/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,ltilve/chromium,Pluto-tv/chromium-crosswalk,Fireblend/chromium-crosswalk,Pluto-tv/chromium-crosswalk,Fireblend/chromium-crosswalk,hgl888/chromium-crosswalk,Chilledheart/chromium,TheTypoMaster/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,Fireblend/chromium-crosswalk,chuan9/chromium-crosswalk,chuan9/chromium-crosswalk,Fireblend/chromium-crosswalk,axinging/chromium-crosswalk,Pluto-tv/chromium-crosswalk,Just-D/chromium-1,Just-D/chromium-1,Chilledheart/chromium,Pluto-tv/chromium-crosswalk,Fireblend/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,Chilledheart/chromium,axinging/chromium-crosswalk,hgl888/chromium-crosswalk,Just-D/chromium-1,chuan9/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,Just-D/chromium-1,Chilledheart/chromium,Fireblend/chromium-crosswalk,hgl888/chromium-crosswalk,Pluto-tv/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,Chilledheart/chromium,chuan9/chromium-crosswalk,chuan9/chromium-crosswalk,Chilledheart/chromium,axinging/chromium-crosswalk,Fireblend/chromium-crosswalk,ltilve/chromium,Chilledheart/chromium,TheTypoMaster/chromium-crosswalk,Just-D/chromium-1,chuan9/chromium-crosswalk,axinging/chromium-crosswalk,ltilve/chromium,chuan9/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,axinging/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,Just-D/chromium-1,Pluto-tv/chromium-crosswalk,ltilve/chromium,Fireblend/chromium-crosswalk,axinging/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,Just-D/chromium-1,Just-D/chromium-1,ltilve/chromium,ltilve/chromium,hgl888/chromium-crosswalk