Test SIN6_LEN instead of OS_MACOSX to determine if sockaddr_in* structures have a sin*_len member.
Test SIN6_LEN instead of OS_MACOSX to determine if sockaddr_in*
structures have a sin*_len member.

The SIN6_LEN macro is required by RFC 3493 Section 3.4.  Since
Chrome requires the IPv6 socket API, it is fine to use SIN6_LEN
for the IPv6 sockaddr_in structure also.

R=agayev@chromium.org,cbentzel@chromium.org,eroman@chromium.org
BUG=none
TEST=none

Review URL: http://codereview.chromium.org/7461105

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@94324 0039d316-1c4b-4281-b951-d872f2087c98

yitian134/chromium,yitian134/chromium,gavinp/chromium,adobe/chromium,gavinp/chromium,yitian134/chromium,ropik/chromium,adobe/chromium,ropik/chromium,yitian134/chromium,ropik/chromium,adobe/chromium,ropik/chromium,adobe/chromium,gavinp/chromium,ropik/chromium,adobe/chromium,gavinp/chromium,gavinp/chromium,ropik/chromium,adobe/chromium,adobe/chromium,yitian134/chromium,yitian134/chromium,ropik/chromium,gavinp/chromium,yitian134/chromium,adobe/chromium,gavinp/chromium,adobe/chromium,adobe/chromium,yitian134/chromium,gavinp/chromium,ropik/chromium,ropik/chromium,yitian134/chromium,gavinp/chromium,gavinp/chromium,yitian134/chromium,adobe/chromium