Fix CORB tests using the wrong references

Problem uncovered by a recent change in WPT, see:
https://bugs.chromium.org/p/chromium/issues/detail?id=844781#c5

Bug: 844781
Change-Id: I6d3a51e7673ef28128b0ede4cbb0450a299730b5
Reviewed-on: https://chromium-review.googlesource.com/1065991
Reviewed-by: Łukasz Anforowicz <lukasza@chromium.org>
Commit-Queue: Philip Jägenstedt <foolip@chromium.org>
Cr-Commit-Position: refs/heads/master@{#560268}
3 files changed