Should `GLSL_EXT_structured_descriptor_heap` blocks allow omitting block/instance names?

1. Block names

The extension spec gives examples such as:

```glsl
resourceheap {
accelerationStructureKHR myAccelerationStructure;
} myResourceHeapView;
```

The GLSL spec does not allow omitting the `block-name` of an `interface-block`. Current `glslang` behavior agrees with the base spec but diverges from some of the examples given in the extension spec, producing the following output:
```
ERROR: :5: '' : syntax error, unexpected LEFT_BRACE
```
Are the examples in the extension spec intended to work as-is?

2. Instance names

It seems that `resourceheap` and `samplerheap` blocks currently require an instance name. If no instance name is provided, the following error is printed:
```
ERROR: :5: 'ResourceHeap' : layout(descriptor_heap) decorated block should be explicitly declared with a run-time sized array type.
```
Is this intended behavior? I think it would stand to reason to allow omitting the instance name, thus making the following two lines more or less equivalent:

```glsl
layout(descriptor_heap) uniform texture2D textures[];
resourceheap TextureHeap { texture2D textures[]; };
```

Start by running the block-name and instance-name examples from the issue through glslang and compare the diagnostics with the GLSL_EXT_structured_descriptor_heap specification. Determine whether each omission is intended, then define the expected compiler behavior and checks needed to confirm the decision.

Written by the indexing model from the issue text.