Filing mostly for discussion. See https://chromium-review.googlesource.com/c/552902/
IMEs are implemented as extensions in //chrome/browser. However, the IME system has to show UI like the candidate window and the little "mode indicator" bubble. These are more like system-ui than browser UI. For example, you can use IMEs to type into the login screen, network connect dialogs, etc.
The candidate window and mode indicator bubble code lives in //ui/chromeos/ime, probably from the Athena days. It used to live in //ash.
For mustash I had to add a delegate to the mode indicator bubble so it can parent itself correctly (it needs to know about ash containers). I think a better solution would be to move this UI code out of //ui/chromeos/ime back into //ash/ime.
Thoughts?
Comment 1 by satorux@chromium.org
, Jul 4 2017