bc38b4d450
Reason for revert: breaks downstream project Original issue's description: > Simplify and extend RtpHeaderExtensionMap > Add register functions for various codepaths. > Add initialize-list constructor to create usable const RtpHeaderExtensionMap > Optimize implementation for GetId/GetType. > > BUG=webrtc:1994 > > Committed: https://crrev.com/d1d26fbeb37a69471a34004c6ac2d3fafde5d404 > Cr-Commit-Position: refs/heads/master@{#14986} TBR=sprang@webrtc.org # Skipping CQ checks because original CL landed less than 1 days ago. NOPRESUBMIT=true NOTREECHECKS=true NOTRY=true BUG=webrtc:1994 Review-Url: https://codereview.webrtc.org/2484863007 Cr-Commit-Position: refs/heads/master@{#14988}