Support new js proposals: optional-chaining & pipeline-operator

Description

NOTE:

• Check the list of open issues before filing a new issue.
• Please update the expect output section to match how you would prefer the code to look.

Input

The code looked like this before beautification:

'test' |> console.log;
let a = {};
a?.b?.c?.d;

Current Output

The code actually looked like this after beautification:

'test' | > console.log;
let a = {};
a ? .b ? .c ? .d;

Expected Output

The code should have looked like this after beautification:

/*Adjust the code to look how you prefer the output to be.*/
'test' |> console.log;
let a = {};
a?.b?.c?.d;

Environment

Browser User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36

Language Selected: JavaScript

Settings

Example:

{
  "indent_size": "4",
  "indent_char": " ",
  "max_preserve_newlines": "5",
  "preserve_newlines": true,
  "keep_array_indentation": false,
  "break_chained_methods": false,
  "indent_scripts": "normal",
  "brace_style": "collapse",
  "space_before_conditional": true,
  "unescape_strings": false,
  "jslint_happy": false,
  "end_with_newline": false,
  "wrap_line_length": "0",
  "indent_inner_html": false,
  "comma_first": false,
  "e4x": false
}

[theblang]

@bitwiseman Looks like proposal-optional-chaining has made it to stage 2!

[bitwiseman]

@theblang Yes, each item should be filed as separate issue that can be tracked to completion.