[llvm] [llvm] Use OwningArrayRef in NodeMetadata (NFC) (PR #137539)

[Kazu Hirata via llvm-commits]

kazutakahirata wrote:

> > > Can we replace the member with OwningArrayRef instead?
> > 
> > 
> > I don't think so. The array could be reallocated in the middle of lifetime:
> 
> OwningArrayRef has operator= so I think that should be ok?

You are right.  I now use `OwningArrayRef` in the latest revision.


https://github.com/llvm/llvm-project/pull/137539