1 files changed, 46 insertions, 0 deletions
diff --git a/layout/reftests/scrolling/scrolling.js b/layout/reftests/scrolling/scrolling.js
new file mode 100644
index 0000000000..2176c90d8d
--- /dev/null
+++ b/layout/reftests/scrolling/scrolling.js
@@ -0,0 +1,46 @@
+var topElements;
+var failed = false;
+
+function doScroll(d)
+{
+  if (failed)
+    return;
+  for (var i = 0; i < topElements.length; ++i) {
+    var e = topElements[i];
+    e.scrollTop = d;
+    if (e.scrollTop != d) {
+      document.documentElement.textContent =
+          "Scrolling failed on " + e.tagName + " element, " +
+          "tried to scroll to " + d + ", got " + e.scrollTop +
+          " (Random number: " + Math.random() + ")";
+      failed = true;
+    }
+  }
+}
+
+// bug 1134459, images are decoded off main thread
+// Wait for the load event so we know all images have loaded
+document.onload = function() {
+  topElements = document.getElementsByClassName("scrollTop");
+  if (!topElements.length) {
+    topElements = [document.documentElement];
+  }
+
+  if (document.location.search == '?ref') {
+    doScroll(20);
+  } else if (document.location.search == '?up') {
+    doScroll(40);
+    document.documentElement.setAttribute("class", "reftest-wait");
+    window.addEventListener("MozReftestInvalidate", function() {
+        document.documentElement.removeAttribute("class");
+        doScroll(20);
+        });
+  } else {
+    doScroll(1);
+    document.documentElement.setAttribute("class", "reftest-wait");
+    window.addEventListener("MozReftestInvalidate", function() {
+        document.documentElement.removeAttribute("class");
+        doScroll(20);
+        });
+  }
+}