Media access permissions can not be changed within the same session

[Ugo Riboni]

Once I reply with allow() or deny() to the mediaAccessPermissionRequested signal from a certain origin, then the signal will not be emitted again while in the same session.
Ideally users should be able to change their opinion about whether or not an origin is trusted with media access without having to restart the browser session.

[Olivier Tilloy (osomon)]

Note that this stems from a concrete use-case: the design for webbrowser-app allows users to modify their preferences for media access per domain. If a user changes her mind about the permissions for a given domain and toggles the corresponding switch in the settings UI, she will expect the browser to respect this decision without having to restart it.