fixed ClippingNode's DrawNode stencil bug on Canvas

When using canvas renderer, DrawNode as ClippingNode stencil, the stencil has wrong coordinates when resizing canvas;

Steps to reproduce:
-set renderer to Canvas ("renderMode" : 1);
-enable autoresize (cc.view.resizeWithBrowserSize(true));
-create some ClippingNode with DrawNode as stencil;
-try to resize window - stencil will strangely change its position;