With the expanding use cases for webrtc::CryptoOptions it makes more sense for it to be be available per peer connection instead of only as a factory option. To support backwards compatability for now this code will support the factory method of setting crypto options by default. However it will completely overwrite these settings if an RTCConfiguration.crypto_options is provided. Got LGTM offline from Sami, adding him to TBR if he has any further comments. TBR=sakal@webrtc.org Bug: webrtc:9891 Change-Id: I86914cab69284ad82afd7285fd84ec5f4f2c4986 Reviewed-on: https://webrtc-review.googlesource.com/c/107029 Commit-Queue: Benjamin Wright <benwright@webrtc.org> Reviewed-by: Seth Hampson <shampson@webrtc.org> Reviewed-by: Patrik Höglund <phoglund@webrtc.org> Reviewed-by: Kári Helgason <kthelgason@webrtc.org> Cr-Commit-Position: refs/heads/master@{#25375}