Reason for revert: Breaks chrome. Original issue's description: > provide RSA2048 as per RFC > > BUG=webrtc:4972 > > Committed: https://crrev.com/0df3eb03c9a6a8299d7e18c8c314ca58c2f0681e > Cr-Commit-Position: refs/heads/master@{#10209} TBR=hbos@webrtc.org,juberti@google.com,jbauch@webrtc.org,henrikg@webrtc.org NOPRESUBMIT=true NOTREECHECKS=true NOTRY=true BUG=webrtc:4972 Review URL: https://codereview.webrtc.org/1397703002 Cr-Commit-Position: refs/heads/master@{#10210}