pull the latest source from chromium

Change-Id: I1b3c58851267826d3322332649799a069891009e
diff --git a/src/shared/css/tree.css.js b/src/shared/css/tree.css.js
new file mode 100644
index 0000000..a6ce38e
--- /dev/null
+++ b/src/shared/css/tree.css.js
@@ -0,0 +1,22 @@
+// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+(function() {
+  var a = 7;
+  var a2 = a / 2;
+  var ctx = document.getCSSCanvasContext('2d', 'tree-triangle', a + 1, a2 + 2);
+
+  ctx.fillStyle = '#000';
+  ctx.translate(.5, .5);
+
+  ctx.beginPath();
+  ctx.moveTo(0, 0);
+  ctx.lineTo(0, 1);
+  ctx.lineTo(a2, 1 + a2);
+  ctx.lineTo(a, 1);
+  ctx.lineTo(a, 0);
+  ctx.closePath();
+  ctx.fill();
+  ctx.stroke();
+})();