Bug 1451257 [wpt PR 10303] - Simplify assert_throws in two places where error message...

Bug 1451257 [wpt PR 10303] - Simplify assert_throws in two places where error messages were passed, a=testonly

Automatic update from web-platform-testsSimplify assert_throws in two places where error messages were passed

This was discovered in
https://chromium-review.googlesource.com/c/chromium/src/+/980757 by
letting assert_throws also check that the message matches. That change
itself isn't a good idea, but it's still just as well to use plain
TypeErrors here to not make it seems like more is being tested than in
fact is.

Change-Id: I8f964e9b25cc94942cb86f3ee0017530f230e04a
Reviewed-on: https://chromium-review.googlesource.com/995192
Reviewed-by: Adam Rice <ricea@chromium.org>
Reviewed-by: Mounir Lamouri <mlamouri@chromium.org>
Commit-Queue: Philip Jägenstedt <foolip@chromium.org>
Cr-Commit-Position: refs/heads/master@{#548060}

wpt-commits: 168e0e121c233c19292757f66fd949a444efffc1
wpt-pr: 10303
wpt-commits: 168e0e121c233c19292757f66fd949a444efffc1
wpt-pr: 10303