Convert to ES2015 class do not recognize inheritance

[Mingun]

Issue Type: Bug

function Derived() {
  Base.call(this, /*some base args*/);
  /* some other constructor work */
};
Derived.prototype = new Base();
Derived.prototype.constructor = Derived;

must be converted to

class Derived extends Base {
  constructor() {
    super(/*some base args*/);
    /* some other constructor work */
  }
}

Right now it converted to

class Derived {
  constructor() {
    Base.call(this, /*some base args*/);
    /* some other constructor work */
  }
}
;
Derived.prototype = new Base();
Derived.prototype.constructor = Derived;

VS Code version: Code 1.36.1 (2213894ea0415ee8c85c5eea0d0ff81ecc191529, 2019-07-08T22:59:35.033Z)
OS version: Windows_NT x64 10.0.17134

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-8550U CPU @ 1.80GHz (8 x 1992)
GPU Status	2d_canvas: enabled flash_3d: enabled flash_stage3d: enabled flash_stage3d_baseline: enabled gpu_compositing: enabled multiple_raster_threads: enabled_on native_gpu_memory_buffers: disabled_software oop_rasterization: disabled_off protected_video_decode: enabled rasterization: enabled skia_deferred_display_list: disabled_off skia_renderer: disabled_off surface_synchronization: enabled_on video_decode: enabled viz_display_compositor: disabled_off webgl: enabled webgl2: enabled
Load (avg)	undefined
Memory (System)	7.89GB (2.36GB free)
Process Argv
Screen Reader	no
VM	0%

Extensions (14)

Extension	Author (truncated)	Version
search-crates-io	bel	1.2.1
better-toml	bun	0.3.2
bracket-pair-colorizer-2	Coe	0.0.28
pegjs-syntax	fut	0.1.1
nwscript	glo	0.0.2
restructuredtext	lex	112.0.0
hg	mrc	1.3.0
vscode-language-pack-ru	MS-	1.36.2
rust	rus	0.6.1
crates	ser	0.4.3
vscode-hexdump	sle	1.7.2
code-spell-checker	str	1.7.17
code-spell-checker-russian	str	0.2.2
sort-lines	Tyr	1.8.0