This CL splits the iOS sdk into separate static libraries for video, audio, ui, common, and peerconnection-related code. This will in the future make it easier to compile WebRTC without unneeded components. BUG=webrtc:4867 Review-Url: https://codereview.webrtc.org/2862543002 Cr-Commit-Position: refs/heads/master@{#18166}