Add ability to configure navigator.userAgentData.brands at runtime

[BrianAndersonMozenda]

Describe the bug
Because the navigator.userAgentData.brands is a internal readonly property it can't be overridden to be able to create a brand browser.

To Reproduce
Steps to reproduce the behavior:

1. Open cefclient
2. Open DevTools
3. Open the Console
4. Type "navigator.userAgentData"
5. Note that the default readonly property is returned

Expected behavior
Have the ability to override the brands property similar to Brave, Chrome, and Edge. We provide a pseudo-browser to our customers and we would like to be able to override these properties.

https://developer.mozilla.org/en-US/docs/Web/API/NavigatorUAData

Screenshots

[magreenblatt]

Branding is a compile-time value from chrome/app/theme/chromium/BRANDING. Currently, you will need to generate your own custom CEF/Chromium builds to configure this.

The NavigatorUIData is populated via GetUserAgentMetadata, so it may also be possible to configure this particular value at runtime with Chromium code changes.

[amaitland]

The following might be worth a try

https://chromedevtools.github.io/devtools-protocol/tot/Emulation/#type-UserAgentBrandVersion