Steps:
Re-parenting currently moves a tab from a CustomTabActivity and makes it owned
by a ChromeTabbedActivity (with an entirely different set of UI).

You can test this by doing something like:
1) Open a link (another language so that you get language prompt) from Gmail
2) It should pop up a picker that lets you choose your locally built Chromium
3) It should appear as a Custom Tab
(https://developer.chrome.com/multidevice/android/customtabs)
4) Select translate option "Always translate" from translate info bar.
5) From the menu, select "open in browser" or something; if your Chromium build is set as your default browser then it should reparent the tab over.

We see the following message then:
Abort message: '[FATAL:view_android.cc(118)] Check failed: !SubtreeHasEventForwarder(child) || !ViewTreeHasEventForwarder(this). Only one event handler is allowed.

Mostly this is not limited to translate infobar, and a generic issue.