The ordering of special cases is incorrect. Our hardcoded "allow mock devices and don't prompt for them" settings are short-circuiting the automation session's getUserMedia permission check.
rdar://problem/35210121
Created attachment 325079 [details] Proposed Fix
LGTM. At some point, we might want to remove mockCaptureDevicesPromptEnabled since WebDriver is a better solution.
Comment on attachment 325079 [details] Proposed Fix Clearing flags on attachment: 325079 Committed r224082: <https://trac.webkit.org/changeset/224082>
All reviewed patches have been landed. Closing bug.