x/tools/gopls: wire up gofumpt option fields with information from the main module

[mvdan]

From internal/hooks/hooks.go, as per https://go-review.googlesource.com/c/tools/+/387374:

    options.GofumptFormat = func(ctx context.Context, src []byte) ([]byte, error) {
        return format.Source(src, format.Options{
            // TODO: fill LangVersion and ModulePath from the current go.mod.
            // The information is availabe as loaded by go/packages via the
            // Module type, but it needs to be wired up all the way here.
            // We likely want to change the GofumptFormat field type to take
            // extra parameters, to then be used in format.Options.
            // See https://pkg.go.dev/mvdan.cc/gofumpt@v0.3.0/format#Options.
        })
    }

This is a tracking issue so we remember to do this hopefully sooner than later. It's not rocket science; we just need to figure out the right way to wire up the information across the involved interfaces and APIs.

Since GitHub doesn't linkify inside blockquotes, by the way: https://pkg.go.dev/mvdan.cc/gofumpt@v0.3.0/format#Options

cc @findleyr

[gopherbot]

Change https://go.dev/cl/387634 mentions this issue: gopls: wire in LangVersion and ModulePath for gofumpt formatting