Convert some repaint tests to not call display()

LayoutTests/media/audio-repaint.html

Index: LayoutTests/media/audio-repaint.html
diff --git a/LayoutTests/media/audio-repaint.html b/LayoutTests/media/audio-repaint.html
index c20333330d6bf5e46ddf34371db17437630eb0ed..699a65a1c6e6868ff570d6771c41190f429b7a71 100644
--- a/LayoutTests/media/audio-repaint.html
+++ b/LayoutTests/media/audio-repaint.html
@@ -7,12 +7,12 @@
 <audio controls autoplay onplaying="playing(1)" src="content/silence.wav" style="margin-bottom:25px; -webkit-box-reflect:below;"></audio><br/>
 <audio controls autoplay onplaying="playing(2)" src="content/silence.wav" style="margin:27px 0; -webkit-transform: rotate(15deg);"></audio><br>
 <script>
+    // Note: can't dump repaint rects here (yet) because this is trying to
+    // test autoplaying and window.internals doesn't exist at the right time
+    // to start tracking repaint rects.
     if (window.testRunner)
         testRunner.waitUntilDone();
 
-    if (window.testRunner)
-        testRunner.display();
-
     var count = 3;
     var audioElements = document.getElementsByTagName('audio');