Custom menubar does not reappear after zen mode

[Ayplow]

Issue Type: Bug

1. set 1"window.titleBarStyle": "custom"` added in [WIP] Colored titlebar for Windows #39972
2. Enable Zen mode
3. Disable Zen mode
4. Notice the menubar (Containing File, Edit, etc) is missing

VS Code version: Code - Insiders 1.25.0-insider (e585e4b, 2018-06-20T08:08:46.972Z)
OS version: Windows_NT x64 10.0.17134

System Info

Item	Value
CPUs	Intel(R) Core(TM) i7-4770S CPU @ 3.10GHz (8 x 3098)
GPU Status	2d_canvas: enabled checker_imaging: disabled_off flash_3d: enabled flash_stage3d: enabled flash_stage3d_baseline: enabled gpu_compositing: enabled multiple_raster_threads: enabled_on native_gpu_memory_buffers: disabled_software rasterization: enabled video_decode: enabled video_encode: enabled webgl: enabled webgl2: enabled
Memory (System)	7.94GB (3.76GB free)
Process Argv	C:\Program Files\Microsoft VS Code Insiders\Code - Insiders.exe
Screen Reader	no
VM	0%

Extensions (23)

Extension	Author (truncated)	Version
project-manager	ale	0.25.2
vscode-custom-css	be5	2.7.1
vscode-icontheme-nomo-dark	be5	1.3.5
path-intellisense	chr	1.4.2
vscode-eslint	dba	1.4.12
githistory	don	0.4.1
gitlens	eam	8.4.1
tslint	eg2	1.0.32
vscode-great-icons	emm	2.1.35
vsc-material-theme	Equ	2.1.0
file-icons	fil	1.0.12
auto-close-tag	for	0.5.6
todo-tree	Gru	0.0.63
beautify	Hoo	1.3.2
discord-vscode	icr	2.6.0
vscode-simple-icons	Lau	1.8.3
python	ms-	2018.5.0
vsliveshare	ms-	0.3.317
debugger-for-chrome	msj	4.6.0
material-icon-theme	PKi	3.5.0
seti-icons	qin	0.1.3
vscode-icons	rob	7.23.0
pdf	tom	0.3.0

(5 theme extensions excluded)

[vscodebot]

(Experimental duplicate detection)
Thanks for submitting this issue. Please also check if it is already covered by an existing one, like:

• Zen mode restore setting restores only full-screen (#44652)
• Zen mode remove top bar (#30567)
• Feature request in Zen Mode! (#48256)