Added telemetry pages for the canvas element.

tools/perf/page_sets/tough_canvas_cases/rendering_throughput/canvas_tough_cases_lib.js

Index: tools/perf/page_sets/tough_canvas_cases/rendering_throughput/canvas_tough_cases_lib.js
diff --git a/tools/perf/page_sets/tough_canvas_cases/rendering_throughput/canvas_tough_cases_lib.js b/tools/perf/page_sets/tough_canvas_cases/rendering_throughput/canvas_tough_cases_lib.js
new file mode 100644
index 0000000000000000000000000000000000000000..676eb1a250fa05e2b99d2edd9100eb006be15954
--- /dev/null
+++ b/tools/perf/page_sets/tough_canvas_cases/rendering_throughput/canvas_tough_cases_lib.js
@@ -0,0 +1,38 @@
+// Copyright 2016 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 Point(x, y) {
+  this.x = x;
+  this.y = y;
+}
+
+function get_random_color_string() {
+  var characters = "0123456789ABCDEF";
+  var color = "#";
+
+  for (var i = 1; i < 7; i++) {
+    color += characters[Math.floor(Math.random() * characters.length)];
+  }
+
+  return color;
+}
+
+function rand_sgn(number) {
+  return Math.floor(Math.random() * 2) ? 1*number : -1*number;
+}
+
+function swap(array, i, j) {
+  var temp = array[i];
+  array[i] = array[j];
+  array[j] = temp;
+}
+
+function shuffle(l) {
+  for (var i = 0; i < l.length -1; i++) {
+    var num_left = l.length - i;
+    var to_swap = i + Math.floor(Math.random() * num_left);
+    swap(l, i, to_swap);
+  }
+}
+