Refactored ViEEncryptionImpl, ViECodecImpl and removed unused SRTP hooks/APIs in ViEEncrption.

Review URL: http://webrtc-codereview.appspot.com/331004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@1262 4adac7df-926f-26a2-2b94-8c16560cd09d
5 files changed