update all webrtc and libjingle code to use the same function and remove extra implementations. BUG= R=andresp@webrtc.org Review URL: https://webrtc-codereview.appspot.com/55439004 Cr-Commit-Position: refs/heads/master@{#9205}
BUG= R=henrika@webrtc.org Review URL: https://webrtc-codereview.appspot.com/52529004 Cr-Commit-Position: refs/heads/master@{#9201}