Convert some pixel tests in fast/canvas into ref tests.

LayoutTests/fast/canvas/canvasDrawingIntoSelf.html

Index: LayoutTests/fast/canvas/canvasDrawingIntoSelf.html
diff --git a/LayoutTests/fast/canvas/canvasDrawingIntoSelf.html b/LayoutTests/fast/canvas/canvasDrawingIntoSelf.html
index 04853c4d21810a445ebc796f8c3856d51f5ebd22..3f39ac8bd2b1a14ee2606e6ae642e82812988372 100644
--- a/LayoutTests/fast/canvas/canvasDrawingIntoSelf.html
+++ b/LayoutTests/fast/canvas/canvasDrawingIntoSelf.html
@@ -1,14 +1,12 @@
-If this renders correctly you should see one big friendly green square.
+<p>If this renders correctly you should see one big friendly green square.</p>
 <canvas id="canvas" width="200" height="200" ></canvas>
 <script>
-if (window.testRunner)
-  testRunner.dumpAsTextWithPixelResults();
-
 var canvas = document.getElementById("canvas");
 var context = canvas.getContext("2d");
+context.imageSmoothingEnabled = false;
 context.fillStyle = 'red';
 context.fillRect(0,0,200,200);
 context.fillStyle = 'green';
 context.fillRect(50,50,100,100);
 context.drawImage(canvas, 50, 50, 100, 100, 0, 0, 200, 200);
-</script>
+</script>