Add 0x0 size check to canvas (#3467)
Add 0x0 size check to canvas (#3467)

* Add 0x0 size check to canvas

Prevents error from being thrown when we try to
invoke context.drawImage with an argument
that is a 0x0 canvas.

Instead we just skip the drawImage.

* Test dimensions on all canvases

* Reuse variable

* Add warning for condition that previously threw exception

palantir/plottable,palantir/plottable,palantir/plottable,palantir/plottable