Reenable dlclose() for InternalUnloadDll on TSan.

Upstream TSan bug has been fixed and dlclose() no longer needs to be
excluded.

R=henrika@webrtc.org
BUG=3895

Review URL: https://webrtc-codereview.appspot.com/30099004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@8016 4adac7df-926f-26a2-2b94-8c16560cd09d
1 file changed