Chrome os:
Version 73.0.3635.0(platform 11377.0.0-18.12.09) dev-channel kevin test
Google_Input_Tools_Version:72.0.20181203.223901082

REPRO STEPS:
1.Sign out ChromeOS.
2.Focus on the password input-box to make Vk pops up.
3.Press physical Ctrl+Shift+Space / Ctrl+Space.

Actual result: 
Password input-box jumps behind the VK.

Note:
This issue not repro if switch keyboard using menu list of VK.