adding check to prevent tint/webcam conflict issue #410

Author: lauren mccarthy

lib/p5.js

@@ -1,4 +1,4 @@
-/*! p5.js v0.3.10 October 28, 2014 */
+/*! p5.js v0.3.10 November 01, 2014 */
 var shim = function (require) {
     window.requestDraw = function () {
       return window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.oRequestAnimationFrame || window.msRequestAnimationFrame || function (callback, element) {
@@ -2230,7 +2230,7 @@ var imageloading_displaying = function (require, core, filters, canvas, constant
         height = img.height;
       }
       var vals = canvas.modeAdjust(x, y, width, height, this._imageMode);
-      if (this._tint) {
+      if (this._tint && img.canvas) {
         this.drawingContext.drawImage(this._getTintedImageCanvas(img), vals.x, vals.y, vals.w, vals.h);
       } else {
         this.drawingContext.drawImage(frame, vals.x, vals.y, vals.w, vals.h);