Bug 1509792 [wpt PR 14231] - Update wpt metadata, a=testonly

wpt-pr: 14231 wpt-type: metadata
2018-11-26 10:42:03 +00:00 · 2018-11-26 10:42:03 +00:00 · d929dd1b99
--- a/testing/web-platform/meta/preload/dynamic-adding-preload-imagesrcset.tentative.html.ini
+++ b/testing/web-platform/meta/preload/dynamic-adding-preload-imagesrcset.tentative.html.ini
@ -0,0 +1,4 @@
+[dynamic-adding-preload-imagesrcset.tentative.html]
+  [Makes sure that a dynamically added preload with imagesrcset works]
+    expected: FAIL
+