wrap parameterless new expressions with params (fixes #169)

[anilanar]

I mimicked UglifyJS except for the last test case with wrapped new expressions.

For new new X().Y().z

UglifyJS output: new((new X).Y().z) wrong butternut output: (new (new X).Y).z correct

To test it, use the following:

class X { 
  constructor() { 
    this.z = 1; 
    this.Y = class { 
      constructor() { 
        this.z = 2;
      }
    };
  }
}

[kzc]

UglifyJS output: new((new X).Y().z) wrong

Using butternut's copy of uglify-js and uglify-es...

$ node_modules/uglify-js/bin/uglifyjs -V
uglify-js 3.0.9

$ echo 'new new X().Y().z' | node_modules/uglify-js/bin/uglifyjs -b
new (new X().Y)().z;

$ echo 'new new X().Y().z' | node_modules/uglify-js/bin/uglifyjs -cm
(new((new X).Y)).z;

$ node_modules/uglify-es/bin/uglifyjs -V
uglify-es 3.0.9

$ echo 'new new X().Y().z' | node_modules/uglify-es/bin/uglifyjs -b
new (new X().Y)().z;

$ echo 'new new X().Y().z' | node_modules/uglify-es/bin/uglifyjs -cm
(new((new X).Y)).z;

[adamdupuis]

Can this be merged?

[anilanar]

@adamdupuis I think the project is on complete halt.