Link to new web-platform-tests.org documentation from our own

docs/testing/web_platform_tests.md

-# Web Platform Tests
+# web-platform-tests
 
 Interoperability between browsers is
 [critical](https://www.chromium.org/blink/platform-predictability) to Chromium's
 mission of improving the web. We believe that leveraging and contributing to a
 shared test suite is one of the most important tools in achieving
 interoperability between browsers. The [web-platform-tests
 repository](https://github.com/w3c/web-platform-tests) is the primary shared
 test suite where all browser engines are collaborating. There's also a
 [csswg-test repository](https://github.com/w3c/csswg-test) for CSS tests, but
 that will [soon be merged into
 web-platform-tests](https://github.com/w3c/csswg-test/issues/1102).
 
 Chromium has 2-way import/export process with the upstream web-platform-tests
 repository, where tests are imported into
 [LayoutTests/external/wpt](../../third_party/WebKit/LayoutTests/external/wpt)
 and any changes to the imported tests are also exported to web-platform-tests.
 
+See http://web-platform-tests.org/ for general documentation on
+web-platform-tests, including tips for writing and reviewing tests.
+
 [TOC]
 
 ## Importing tests
 
 Chromium has mirrors
 ([web-platform-tests](https://chromium.googlesource.com/external/w3c/web-platform-tests/),
 [csswg-test](https://chromium.googlesource.com/external/w3c/csswg-test/)) of the
 GitHub repos, and periodically imports a subset of the tests so that they are
 run as part of the regular Blink layout test testing process.
 
-The goal of this process are to be able to run Web Platform Tests unmodified
+The goal of this process are to be able to run web-platform-tests unmodified
 locally just as easily as we can run the Blink tests, and ensure that we are
-tracking tip-of-tree in the Web Platform Tests repository as closely as
+tracking tip-of-tree in the web-platform-tests repository as closely as
 possible, and running as many of the tests as possible.
 
 ### Automatic import process
 
-There is an automatic process for updating the Chromium copy of the Web Platform
-Tests. The import is done by the builder [w3c-test-autoroller
+There is an automatic process for updating the Chromium copy of
+web-platform-tests. The import is done by the builder [w3c-test-autoroller
 builder](https://build.chromium.org/p/chromium.infra.cron/builders/w3c-test-autoroller).
 
 The easiest way to check the status of recent imports is to look at:
 
 -   Recent logs on Buildbot for [w3c-test-autoroller
     builder](https://build.chromium.org/p/chromium.infra.cron/builders/w3c-test-autoroller)
 -   Recent CLs created by
     [blink-w3c-test-autoroller@chromium.org](https://codereview.chromium.org/search?owner=blink-w3c-test-autoroller%40chromium.org).
 
 Automatic imports are intended to run at least once every 24 hours.
@@ skipping 24 matching lines @@
 
 If you wish to add more tests (by un-skipping some of the directories currently
 skipped in `W3CImportExpectations`), you can modify that file locally and commit
 it, and on the next auto-import, the new tests should be imported.
 
 If you want to import immediately (in order to try the tests out locally, etc)
 you can also run `wpt-import --allow-local-commits`, but this is not required.
 
 ## Writing tests
 
-To contribute changes to Web Platform Tests, just commit your changes directly
+To contribute changes to web-platform-tests, just commit your changes directly
 to [LayoutTests/external/wpt](../../third_party/WebKit/LayoutTests/external/wpt)
 and the changes will be automatically upstreamed within 24 hours.
 
 Changes involving adding, removing or modifying tests can all be upstreamed.
 Any changes outside of
 [external/wpt](../../third_party/WebKit/LayoutTests/external/wpt) will not be
 upstreamed, and any changes `*-expected.txt`, `OWNERS`, and `MANIFEST.json`,
 will also not be upstreamed.
 
 Note: if you're adding a new test in `external/wpt`, you'll need to re-generate
 MANIFEST.json manually until [CL 2644783003](https://crrev.com/2644783003) is
 landed. The command to do so is:
 
 ```bash
 Tools/Scripts/webkitpy/thirdparty/wpt/wpt/manifest --work \
     --tests-root=LayoutTests/external/wpt
 ```
 
 Most tests are written using testharness.js, see
 [Writing Layout Tests](./writing_layout_tests.md) and
 [Layout Tests Tips](./layout_tests_tips.md) for general guidelines.
 
 ### Write tests against specifications
 
-Tests in Web Platform Tests are expected to match behavior defined by the
+Tests in web-platform-tests are expected to match behavior defined by the
 relevant specification. In other words, all assertions that a test makes
 should be derived from a specification's normative requirements, and not go
 beyond them. It is often necessary to change the specification to clarify what
 is and isn't required.
 
 When the standards discussion is still ongoing or blocked on some implementation
 successfully shipping the hoped-for behavior, write the tests outside of
 web-platform-tests and upstream them when the specification is finally updated.
 Optionally, it may be possible to write deliberately failing tests against the
 current specification and later update them.
@@ skipping 30 matching lines @@
 
 ### What if there are conflicts?
 
 This cannot be avoided entirely as the two repositories are independent, but
 should be rare with frequent imports and exports. When it does happen, manual
 intervention will be needed and in non-trivial cases you may be asked to help
 resolve the conflict.
 
 ### Direct pull requests
 
-It's still possible to make direct pull requests to web-platform-tests. The
-processes for getting new tests committed the W3C repos are at
-http://testthewebforward.org/docs/. Some specifics are at
-http://testthewebforward.org/docs/github-101.html.
+It's still possible to make direct pull requests to web-platform-tests, see
+http://web-platform-tests.org/appendix/github-intro.html.
 
 ## Reviewing tests
 
 Anyone who can review code and tests in Chromium can also review changes in
 [external/wpt](../../third_party/WebKit/LayoutTests/external/wpt)
 that will be automatically upstreamed. There will be no additional review in
 web-platform-tests as part of the export process.
 
 If upstream reviewers have feedback on the changes, discuss on the pull request
 created during export, and if necessary work on a new pull request to iterate
 until everyone is satisfied.
 
 When reviewing tests, check that they match the relevant specification, which
 may not fully match the implementation. See also
 [Write tests against specifications](#Write-tests-against-specifications).