Make the NSS SSL state a Leaky LazyInstance

Because NSS SSL may be used on worker threads, make the associated
LazyInstance used to initialize NSS Leaky.

BUG=none
R=wtc

Review URL: https://codereview.chromium.org/112163006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@242826 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 242826