Add tests for WGPU_ARRAY_SLICE_UNDEFINED and friends.

[Kangz]

I'm seeing this one test webgpu:api,validation,render_pass,render_pass_descriptor:color_attachments,depthSlice,definedness:dimension="2d" fail in dawn.node because the UNDEFINED values in webgpu.h is not handled, however dawn.node doesn't handle any of the UNDEFINED values, so the other tests should fail as well.

[kainino0x]

We definitely test some of the dictionary members that are optional or have defaults. Is dawn.node handling some of the defaults in the generated code layer and missing others that need to be manually handled? Otherwise I'm surprised we haven't noticed problems eariler.

[Kangz]

This issue is that we should also test UINT32_MAX because it has a specific meaning in webgpu.h and could be forgotten in some implementations in their handling of mipLevelCount / arrayLayerCount etc. The depthSlice test correctly checks this but I believe that it is the only one (I just checked that dawn.node doesn't handle UINT32_MAX mipLevelCount/ArrayLayerCount).