Chrome Version       : 73.0.3628.0
OS Version: 10.0


What steps will reproduce the problem?
1. Enable accent colour titlebars in Windows 10.
2. Install a theme that does not override titlebar colours, for example a theme with the below manifest.json :

{
    "manifest_version": 2,

    "name": "Blank Theme",
    "description": "Blank",
    "version": "0.1.0",

    "theme": {
    }
}


What is the expected result?
The theme should show an accent coloured titlebar. Here is a picture of Chrome without a theme installed; this is what Chrome should now look like. https://i.imgur.com/BaRfat9.png


What happens instead of that?
The titlebar colour is instead set to the default grey, as if Windows 10 accent colour titlebars were disabled: https://i.imgur.com/2yJZCuO.png


Please provide any additional information below. Attach a screenshot if
possible.
If you set the "Custom-drawn Windows 10 titlebar" flag to Disabled, then the accent-coloured titlebar will appear - though this is less than ideal for obvious reasons.


UserAgentString: Mozilla/5.0 (Windows NT 10.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/73.0.3628.0 Safari/537.36