Use brace_style for struct instantiation

[Iron-E]

New struct instances don't adhere to brace_style. For example, when brace_style = "AlwaysNextLine", a new struct instance will look like this:

let value = MyStruct {
    something: 1
}

When it should look like this:

let value = MyStruct
{
    something: 1
}

---

Originally posted by @Sibz in #3376 (comment)

[Iron-E]

This also applies when using macro variables:

$foo {
  bar: 1
}

---

Edit: looks like the above is a also related to:

let foo = {
  3
};

And:

foo.bar({
  3
});

Blocks without a context (like unsafe) don't get put on the next line

[calebcartwright]

Thanks for opening all these, but I'm going to close all of them, at least for the time being, pending conclusion of the strategy discussion in #3376

[Iron-E]

Alright. Perhaps given the introduction of a new option fitting this scope they can be reopened 👍