[whatwg] putImageData

[Oliver Hunt]

I was just doing some putImageData tests last night, and found that  
firefox does not allow putImageData to specify a target that extends  
beyond the bounds of the canvas.  Given that getImageData can request  
bounds that extend beyond the canvas region (3.14.11.1.10) I would  
expect to be able to use putImageData in a similar manner, eg.
canvas.putImageData(canvas.getImageData(-50,-50,200,200), -50, -50)
should succeed.

I'd just like the spec to state clearly that this should (or, i  
suppose, should not :( ) work as "Expected", and allow putImageData  
to work as getImageData does.

--Oliver