UserAgent: Mozilla/5.0 (X11; CrOS armv7l 10032.59.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.70 Safari/537.36
Platform: 10032.59.0 (Official Build) beta-channel veyron_minnie

Steps to reproduce the problem:
1. Open TestNav application
2. Login with these credentials:
   - Username: LGN157154218
   - Password: HHZXRXTR
3. Click Start >>
4. Click Start
5. Tab to one of the selects, open via Enter, arrow down to focus any one of the options
6. Press the Browser Back button on the Chromebook keyboard
7. The webview navigates to the landing page for the app, but the application is intercepting and blocking the Browser Back button.

What is the expected behavior?
The browser navigation buttons should have no affect within the app even if focus is within a select.

What went wrong?
The browser navigation buttons cause navigation within the app when focus is within a select.

Did this work before? N/A 

Chrome version: 63.0.3239.70  Channel: beta
OS Version: 10032.59.0
Flash Version: