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+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test that scaled elements with scrolled contents don't repaint unnecessarily when we scroll inside them</title>
+  <script type="text/javascript" src="/tests/SimpleTest/paint_listener.js"></script>
+</head>
+<!-- Need a timeout here to allow paint unsuppression before we start the test -->
+<body onload="setTimeout(startTest,0)" style="background:white;">
+<iframe id="t" style="-moz-transform: scale(0.48979); -moz-transform-origin:top left; width:500px; height:600px;"
+        src="data:text/html,
+<body style='background:yellow;'>
+<p>My graduate adviser was the most patient, understanding, and helpful
+person I've ever had the joy of dealing with. That doesn't change that 
+there are some real dicks out there, and some of them happen to be 
+scientists.
+<p id='e'>My graduate adviser was the most patient, understanding, and helpful
+person I've ever had the joy of dealing with. That doesn't change that 
+there are some real dicks out there, and some of them happen to be 
+scientists.
+<p>My graduate adviser was the most patient, understanding, and helpful
+person I've ever had the joy of dealing with. That doesn't change that 
+there are some real dicks out there, and some of them happen to be 
+scientists.
+<p>My graduate adviser was the most patient, understanding, and helpful
+person I've ever had the joy of dealing with. That doesn't change that 
+there are some real dicks out there, and some of them happen to be 
+scientists.
+<p>My graduate adviser was the most patient, understanding, and helpful
+person I've ever had the joy of dealing with. That doesn't change that 
+there are some real dicks out there, and some of them happen to be 
+scientists.
+<p>My graduate adviser was the most patient, understanding, and helpful
+person I've ever had the joy of dealing with. That doesn't change that 
+there are some real dicks out there, and some of them happen to be 
+scientists.
+<p>My graduate adviser was the most patient, understanding, and helpful
+person I've ever had the joy of dealing with. That doesn't change that 
+there are some real dicks out there, and some of them happen to be 
+scientists.
+<p>My graduate adviser was the most patient, understanding, and helpful
+person I've ever had the joy of dealing with. That doesn't change that 
+there are some real dicks out there, and some of them happen to be 
+scientists.
+<p>My graduate adviser was the most patient, understanding, and helpful
+person I've ever had the joy of dealing with. That doesn't change that 
+there are some real dicks out there, and some of them happen to be 
+scientists.
+<p>My graduate adviser was the most patient, understanding, and helpful
+person I've ever had the joy of dealing with. That doesn't change that 
+there are some real dicks out there, and some of them happen to be 
+scientists.
+<p>My graduate adviser was the most patient, understanding, and helpful
+person I've ever had the joy of dealing with. That doesn't change that 
+there are some real dicks out there, and some of them happen to be 
+scientists.
+<p>My graduate adviser was the most patient, understanding, and helpful
+person I've ever had the joy of dealing with. That doesn't change that 
+there are some real dicks out there, and some of them happen to be 
+scientists.
+<p>My graduate adviser was the most patient, understanding, and helpful
+person I've ever had the joy of dealing with. That doesn't change that 
+there are some real dicks out there, and some of them happen to be 
+scientists.
+<p>My graduate adviser was the most patient, understanding, and helpful
+person I've ever had the joy of dealing with. That doesn't change that 
+there are some real dicks out there, and some of them happen to be 
+scientists.
+</body>"></iframe>
+<pre id="test">
+<script type="application/javascript">
+var SimpleTest = window.opener.SimpleTest;
+var SpecialPowers = window.opener.SpecialPowers;
+var is = window.opener.is;
+var t, e, utils, iterations;
+var smoothScrollPref = "general.smoothScroll";
+
+function startTest() {
+  SpecialPowers.pushPrefEnv({"set":[[smoothScrollPref, false]]}, runTest);
+}
+function runTest() {
+    t = document.getElementById("t");
+    e = t.contentDocument.getElementById("e");
+    t.contentWindow.scrollTo(0,0);
+    utils = SpecialPowers.getDOMWindowUtils(window);
+    iterations = 0;
+
+  // Do a couple of scrolls to ensure we've triggered activity heuristics.
+    waitForAllPaintsFlushed(function () {
+      t.contentWindow.scrollByLines(1);
+      waitForAllPaintsFlushed(function () {
+        t.contentWindow.scrollByLines(1);
+        waitForAllPaintsFlushed(function () {
+          // Clear paint state now and scroll again.
+          utils.checkAndClearPaintedState(e);
+          t.contentWindow.scrollByLines(1);
+          waitForAllPaintsFlushed(nextIteration);
+        });
+      });
+    });
+}
+function nextIteration() {
+  var painted = utils.checkAndClearPaintedState(e);
+  is(painted, false, "Fully-visible scrolled element should not have been painted");
+  if (++iterations == 10) {
+    SimpleTest.finish();
+    window.close();
+  } else {
+    t.contentWindow.scrollByLines(1);
+    waitForAllPaintsFlushed(nextIteration);
+  }
+}
+</script>
+</pre>
+</body>
+</html>