UserAgent: Mozilla/5.0 (X11; CrOS x86_64 9460.60.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/59.0.3071.91 Safari/537.36
Platform: 9460.60.0 (Official Build) stable-channel link

Steps to reproduce the problem:
1. Connect an external USB keyboard to a Chromebook.
2. Install and run the Chrome Key Event Tester app (https://chrome.google.com/webstore/detail/chrome-key-event-tester/amndppkiecbdmiaihgbicalhabkkhhpk?hl=en)
3.Press and release Caps Lock key on the external keyboard.

What is the expected behavior?
There should be keydown and keyup events:
+CapsLock-Capslock

What went wrong?
Only keydown event is generated:
+CapsLock

Debug log:
1693:JavaScript 'keydown' event = {"type":"keydown","charCode":0,"keyCode":20,"repeat":false,"code":"CapsLock"}
1695:PNaCl KeyboardInputEvent = {"type":"KEYDOWN","modifiers":512,"keyCode":20,"characterText":"","code":"CapsLock"}

Did this work before? Yes 58

Chrome version: 59.0.3071.91  Channel: stable
OS Version: 9460.60.0
Flash Version: Shockwave Flash 26.0 r0

This works correctly in the Chrome browser on Windoews platform.
Also, this bug can be observed in CRD https://chrome.google.com/webstore/detail/chrome-remote-desktop/gbchcmhmhahfdphkhkmpfmihenigjmpp?hl=en): 
If you press CapsLock once on an external keyboard, the remote session will be stuck in Caps mode.