[LayoutStability] Move layout tests to WPT

Bug: 581518
Change-Id: I475757c9dc66e192275b1ae02353f15a1fc8f926
Reviewed-on: https://chromium-review.googlesource.com/c/1468581
Reviewed-by: Steve Kobes <skobes@chromium.org>
Commit-Queue: Nicolás Peña Moreno <npm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#631861}
diff --git a/third_party/blink/web_tests/http/tests/performance-timing/layout-jank/buffer-layout-jank.html b/third_party/blink/web_tests/external/wpt/layout-stability/buffer-layout-jank.html
similarity index 94%
rename from third_party/blink/web_tests/http/tests/performance-timing/layout-jank/buffer-layout-jank.html
rename to third_party/blink/web_tests/external/wpt/layout-stability/buffer-layout-jank.html
index c9cfd05..f5818cf 100644
--- a/third_party/blink/web_tests/http/tests/performance-timing/layout-jank/buffer-layout-jank.html
+++ b/third_party/blink/web_tests/external/wpt/layout-stability/buffer-layout-jank.html
@@ -9,7 +9,7 @@
 <script src="/resources/testharness.js"></script>
 <script src="/resources/testharnessreport.js"></script>
 <!-- Delay onload by inserting a slow image.-->
-<img src="/resources/slow-image.php?name=notthere.png&mimeType=image&sleep=3000">
+<img src="resources/slow-image.py">
 <script>
   async_test(function (t) {
     // Modify the position of the div.
diff --git a/third_party/blink/web_tests/http/tests/performance-timing/layout-jank/observe-layoutjank.html b/third_party/blink/web_tests/external/wpt/layout-stability/observe-layoutjank.html
similarity index 100%
rename from third_party/blink/web_tests/http/tests/performance-timing/layout-jank/observe-layoutjank.html
rename to third_party/blink/web_tests/external/wpt/layout-stability/observe-layoutjank.html
diff --git a/third_party/blink/web_tests/external/wpt/layout-stability/resources/slow-image.py b/third_party/blink/web_tests/external/wpt/layout-stability/resources/slow-image.py
new file mode 100644
index 0000000..ee7988c
--- /dev/null
+++ b/third_party/blink/web_tests/external/wpt/layout-stability/resources/slow-image.py
@@ -0,0 +1,6 @@
+import time
+
+def main(request, response):
+    # Sleep for 3s to delay onload.
+    time.sleep(3)
+    return [], ""
\ No newline at end of file
diff --git a/third_party/blink/web_tests/http/tests/performance-timing/layout-jank/supported-layout-type.html b/third_party/blink/web_tests/external/wpt/layout-stability/supported-layout-type.html
similarity index 100%
rename from third_party/blink/web_tests/http/tests/performance-timing/layout-jank/supported-layout-type.html
rename to third_party/blink/web_tests/external/wpt/layout-stability/supported-layout-type.html