Ensure cancelAnimFrame has no function context

diff --git a/src/Chart.Core.js b/src/Chart.Core.js
index f5af352d43e1ffc67983a35d9a7293ce4deb8fa0..efe9f78a8fe26d3d74973ad06906a243796f1cfc 100755 (executable)
--- a/src/Chart.Core.js
+++ b/src/Chart.Core.js
@@ -825,7 +825,7 @@
                },
                stop : function(){
                        // Stops any current animation loop occuring
-                       helpers.cancelAnimFrame(this.animationFrame);
+                       cancelAnimFrame(this.animationFrame);
                        return this;
                },
                resize : function(callback){