Remove unnecessary RAF from tests.

third_party/WebKit/LayoutTests/intersection-observer/same-document-no-root.html

Index: third_party/WebKit/LayoutTests/intersection-observer/same-document-no-root.html
diff --git a/third_party/WebKit/LayoutTests/intersection-observer/same-document-no-root.html b/third_party/WebKit/LayoutTests/intersection-observer/same-document-no-root.html
index 38e043ec1abff23dc45c050bb65506b3a2732671..d70bccf3677c241fbb66d8603df08220719110de 100644
--- a/third_party/WebKit/LayoutTests/intersection-observer/same-document-no-root.html
+++ b/third_party/WebKit/LayoutTests/intersection-observer/same-document-no-root.html
@@ -9,7 +9,6 @@
   description("Simple intersection observer test with no explicit root and one document.");
   var target = document.getElementById("target");
   var entries = [];
-
   observer_callback = function(changes) {
     for (var i in changes)
       entries.push(changes[i]);
@@ -17,16 +16,11 @@
   var observer = new IntersectionObserver(observer_callback, {});
   observer.observe(target);
 
-  // TODO(szager): It shouldn't be necessary to RAF after the call to observer()
-  // and before changing the scroll position, but it is.
-
-  function step0() {
-    setTimeout(function() {
-      shouldBeEqualToNumber("entries.length", 0);
-      document.scrollingElement.scrollTop = 300;
-      requestAnimationFrame(step1);
-    });
-  }
+  onload = function() {
+    shouldBeEqualToNumber("entries.length", 0);
+    document.scrollingElement.scrollTop = 300;
+    requestAnimationFrame(step1);
+  };
 
   function step1() {
     setTimeout(function() {
@@ -76,5 +70,4 @@
     });
   }
 
-  requestAnimationFrame(step0);
 </script>