Recent WebRTC stats spec changes have added restrictions on what stats are available to JavaScript. This is done to reduce that fingerprinting surface of WebRTC getStats. For example, stats exposing hardware capabilities have requirements that must be met by the browser. See [1] for more details. This CL adds the types and the enumerations. Stats with these restrictions should not be added until Chromium has implemented filtering based on the stat type. [1] https://w3c.github.io/webrtc-stats/#limiting-exposure-of-hardware-capabilities Bug: webrtc:14546 Change-Id: I6dae5d4921c7a2bc828a4fc8f7d68e0c59f3be82 Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/279043 Commit-Queue: Evan Shrubsole <eshr@webrtc.org> Reviewed-by: Henrik Boström <hbos@webrtc.org> Cr-Commit-Position: refs/heads/main@{#38381}