Spine gui node is not rendered if size is zero in compiled binaries

[matgis]

Describe the bug (REQUIRED)
If a Spine gui NodeDesc has a zero size (or size is not specified at all) in the compiled binaries for a gui scene the node will not render. If on the other hand the size is stored as any non-zero area (for example 1x1 pixels), the node will render with the actual size.

Unless size = [1 1 0 0] is written to the compiled binaries, the nodes will not render.

To Reproduce (REQUIRED)
Steps to reproduce the behavior:

1. Create a gui with a Spine node.
2. Modify the .gui file in a text editor and set the size of the Spine node to 0, or remove the size property altogether.
3. Build and run the project using Bob.

Expected behavior (REQUIRED)
The size value should be ignored for Spine scenes, since they are auto-sized.

Defold version (REQUIRED):

• Version 1.4.1

Platforms (REQUIRED):

• Platforms: All