Revert "Create a in-memory DTLS identity store that keeps a free identity generated in the background."

Test failure: http://chromegw/i/client.webrtc/builders/Linux32%20Release/builds/3557

This reverts commit df512cc8b73ff519dcdf63a2603ab312d3443402.

TBR=andrew@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/41089004

Cr-Commit-Position: refs/heads/master@{#8579}
git-svn-id: http://webrtc.googlecode.com/svn/trunk@8579 4adac7df-926f-26a2-2b94-8c16560cd09d
12 files changed