For --mash we use BrowserNonClientFrameViewMash. BrowserNonClientFrameViewMash was forked from BrowserNonClientFrameViewAsh a long time ago, and as a result is seriously SERIOUSLY out of date. I think we should try to use BrowserNonClientFrameViewAsh in --mash as well. This may mean more conditionals in BrowserNonClientFrameAsh, but this seems more sustainable in the near term.
I suspect this is a fair amount of work, and I wouldn't try addressing immersive just yet. We may want to create a bunch of smaller bugs that are blocking this.
Comment 1 by est...@chromium.org
, Jun 22 2018