This patch introduce a new AssertMatchInternal to ExtensionTest, this method isn't exposed to
js callers through the webidl definition, it is meant to be used internally by the
AssertThrows and AssertRejects methods (which are instead both methods part of the ExtensionTest
webidl).
This patch also introduces small changes to ExtensionAPIRequestForwarder and RequestWorkerRunnable,
to allow AssertMatchInternal to accept as an optional parameter a serialized caller stack trace
(to be sent as part of the APIRequest forwarded from the worker thread to the main thread),
which is needed for AssertRejects (to include the strack trace retrieved when AssertRejects is
called, and then after the promise parameter has been rejected or resolved to send it as part
of the forwarded aPI request).
Differential Revision: https://phabricator.services.mozilla.com/D122033
4900365b51