Light shadows don't always follow the vertex shader changes

[capnm]

Godot 2cde466

The vertices of the default sphere mesh are changed in the vertex shader. Without an external
animation, the shadow does not refresh the shape. It happens in both the editor and the app.

The workaround is to add a small translation animation to the spatial node. See the test below, the translation ends after 5s:

[capnm]

The directional light works now.

i15617-vertex-shader-schadow.zip