ToProgram() will most likely be conditionally compiled as a separate .h
and .cc file. With just one static method, ir::Converter doesn't make a
lot of sense to be a class. Just replace with a free-function.
Bug: tint:1902
Change-Id: I305bf9cb73082a94848ec5b94129feabdb9b6fe9
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/131620
Commit-Queue: Ben Clayton <bclayton@google.com>
Reviewed-by: Dan Sinclair <dsinclair@chromium.org>
Kokoro: Kokoro <noreply+kokoro@google.com>
