Bug 1548057 - Crashtest. r=boris

This crashes both debug and opt builds pretty badly without the fix for this bug. Differential Revision: https://phabricator.services.mozilla.com/D29497 --HG-- extra : moz-landing-system : lando
2019-05-02 07:32:26 +00:00 · 2019-05-02 07:32:26 +00:00 · aaaed5755e
--- a/layout/base/crashtests/1548057.html
+++ b/layout/base/crashtests/1548057.html
@ -0,0 +1,42 @@
+<!doctype html>
+<html class="reftest-wait">
+<body>
+<script>
+  let parentDoc = `
+    <!doctype html>
+    <script>
+    onload = function() {
+      let observer = new ResizeObserver(_ => {
+        let parentFrame = window.parent.document.querySelector("iframe");
+        parentFrame.getBoundingClientRect();
+        parentFrame.style.display = "none";
+        parentFrame.getBoundingClientRect();
+        parentFrame.srcdoc = ""; // Navigate ourselves away.
+      });
+
+      setTimeout(() => observer.observe(document.documentElement), 0);
+    }
+  </` + 'script>';
+  let iframe = document.createElement("iframe");
+  iframe.srcdoc = parentDoc;
+  iframe.onload = function() {
+    if (this.srcdoc !== "") // We're only interested on the second load.
+      return;
+    SpecialPowers.forceGC();
+    SpecialPowers.forceCC();
+    requestAnimationFrame(() => {
+      requestAnimationFrame(() => {
+        SpecialPowers.forceGC();
+        SpecialPowers.forceCC();
+        iframe.style.display = "";
+        requestAnimationFrame(() => {
+          requestAnimationFrame(() => {
+            // If we haven't crashed by now, we should be fine.
+            document.documentElement.className = "";
+          })
+        })
+      })
+    });
+  };
+  document.body.appendChild(iframe);
+</script>
--- a/layout/base/crashtests/crashtests.list
+++ b/layout/base/crashtests/crashtests.list
@ -570,3 +570,4 @@ pref(layout.css.column-span.enabled,true) load 1539017.html
 load 1539303.html
 pref(layout.css.column-span.enabled,true) load 1541679.html
 load 1547261.html
+pref(layout.css.resizeobserver.enabled,true) load 1548057.html