1 files changed, 51 insertions, 0 deletions
diff --git a/layout/base/tests/test_resize_flush.html b/layout/base/tests/test_resize_flush.html
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+++ b/layout/base/tests/test_resize_flush.html
@@ -0,0 +1,51 @@
+<!DOCTYPE HTML>
+<html>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=1279202
+-->
+<head>
+  <title>Test for Bug 1279202</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body onload="run()">
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1279202">Mozilla Bug 1279202</a>
+<iframe src="resize_flush_iframe.html" id="iframe" height="200" width="200" style="border:none"></iframe>
+<pre id="test">
+<script type="application/javascript">
+
+/** Test for Bug 1279202 **/
+
+SimpleTest.waitForExplicitFinish();
+
+function run() {
+
+  var iframe = document.getElementById("iframe");
+  var doc = iframe.contentDocument.documentElement;
+  var win = iframe.contentWindow;
+  var body = iframe.contentDocument.body;
+
+  // Flush any pending layout changes before we start.
+  var width = doc.clientWidth;
+
+  // Resize the iframe
+  iframe.width = '300px';
+
+  // Flush pending style changes, but not layout ones. We do this twice because the first flush
+  // does a partial flush of the resize (setting the size on the pres context) which sets the
+  // need style flush flag again. The second call makes sure mNeedStyleFlush is false.
+  var color = win.getComputedStyle(body).getPropertyValue("background-color");
+  color = win.getComputedStyle(body).getPropertyValue("background-color");
+  is(color, "rgb(0, 128, 0)", "Style flush not completed when resizing an iframe!");
+
+  // Query the size of the inner document and make sure it has had a layout flush.
+  width = doc.clientWidth;
+
+  is(width, 300, "Layout flush not completed when resizing an iframe!");
+  SimpleTest.finish();
+}
+
+</script>
+</pre>
+</body>
+</html>