tree 2e12823a33950dcbbe11bc53eb21faddfe2f4f43
parent 3d053e1672802108dd711f18055db4dc479ef448
author Karl Tomlinson <karlt+@karlt.net> 1574022963 +0000
committer jgraham <james@hoppipolla.co.uk> 1576251575 +0000

close MessagePort after 'recordfinished' is sent

so that 'recordfinished' is not sent again.

Additional messages posted are dropped without error.

`close()`ing to disentangle the MessagePort is also good practice as it allows
GC of otherwise unused objects.

Differential Revision: https://phabricator.services.mozilla.com/D53100

bugzilla-url: https://bugzilla.mozilla.org/show_bug.cgi?id=1596594
gecko-commit: 06248120ae60f264025c41a0cf6c62967b659b34
gecko-integration-branch: autoland
gecko-reviewers: padenot