Just in case people weren't aware, there's automatic two-way sync via the LayoutTests/external/wpt/ directory, so you don't have to use GitHub at all if you don't want to.

mtrofin@, do you plan to work on this soon?

I ask because we seem to have a window of opportunity here. Everybody is implementing wasm right now, and if we share tests then we can avoid accidental interop problems. If the tests are shared too late, then all the vendors individually will already have invested in their own test suites, and crucially some trivial and unnecessary differences may have already shipped to users.

It's on my radar, but there are a few higher priority items I'm currently working on. Having said that, the move isn't particularly tricky either, from what I've seen. I should have some time next week.

postMessage and IDB tests:

https://chromium-review.googlesource.com/c/523033/

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/0f98b21f2bf448e683c66414f79cb5a8b0786c82

commit 0f98b21f2bf448e683c66414f79cb5a8b0786c82
Author: Mircea Trofin <mtrofin@chromium.org>
Date: Mon Jun 05 22:35:05 2017

[wasm] move out of wpt chrome-specific downgrade test.

Testing downgrades uses chrome-specific internal test APIs.

Also removed redundant comment about a utility wasm file.

Bug: chromium:724151
Change-Id: I8c690de0c5884ad3323c8d634691330860f2aee6
Reviewed-on: https://chromium-review.googlesource.com/524575
Commit-Queue: Brad Nelson <bradnelson@chromium.org>
Reviewed-by: Brad Nelson <bradnelson@chromium.org>
Cr-Commit-Position: refs/heads/master@{#477100}
[modify] https://crrev.com/0f98b21f2bf448e683c66414f79cb5a8b0786c82/third_party/WebKit/LayoutTests/external/wpt/wasm/resources/load_wasm.js
[modify] https://crrev.com/0f98b21f2bf448e683c66414f79cb5a8b0786c82/third_party/WebKit/LayoutTests/external/wpt/wasm/wasm_serialization_tests.html
[modify] https://crrev.com/0f98b21f2bf448e683c66414f79cb5a8b0786c82/third_party/WebKit/LayoutTests/external/wpt/wasm/wasm_serialization_tests.js
[add] https://crrev.com/0f98b21f2bf448e683c66414f79cb5a8b0786c82/third_party/WebKit/LayoutTests/http/tests/wasm/wasm_downgrade_test.html
[add] https://crrev.com/0f98b21f2bf448e683c66414f79cb5a8b0786c82/third_party/WebKit/LayoutTests/http/tests/wasm/wasm_downgrade_test.js