Fix: arrow-body-style crash with object literal body (fixes #12884)

[mdjermanovic]

Prerequisites checklist

• I have read the contributing guidelines.
• The team has reached consensus on the changes proposed in this pull request. If not, I understand that the evaluation process will begin with this pull request and won't be merged until the team has reached consensus.

What is the purpose of this pull request? (put an "X" next to an item)

[x] Bug fix

Fixes #12884

arrow-body-style autofix crashes or produces invalid code while trying to convert object literal expression body to a block body, whenever ( and { are not adjacent:

• This works well: () => ({})
• This throws (there's a space between): () => ( {}) Demo
• This removes the wrong closing paren: (() => ( {})) fixed to (() => {return {})} Demo

What changes did you make? (Give an overview)

Fixed to code to pass the brace token instead of the paren token to sourceCode#getNodeByRangeIndex

Is there anything you'd like reviewers to focus on?

In this branch, auto-fixer has also to account for the ASI (it used to crash in all situations where ASI can happen, so it wasn't observable). In particular, for a code where ( and { are not on the same line. This is solved by replacing ( with a block { and inserting return before the object's {. Is it okay?

The code from the original issue:

/* eslint  "arrow-body-style": ["error", "always"] */

parsedYears     = _map(years, (year) => (
      {
          index : year,
          title : splitYear(year)
      }
));

will be auto-fixed to:

/* eslint  "arrow-body-style": ["error", "always"] */

parsedYears     = _map(years, (year) => {
      return {
          index : year,
          title : splitYear(year)
      }
});

[kaicataldo]

LGTM, thanks!