Implement ignoreKeyboardLayout option in getKeyChar.
Implement ignoreKeyboardLayout option in getKeyChar.

Fixes #2618.

poacher2k/vimium,poacher2k/vimium,philc/vimium,mrmr1993/vimium,decaffeinate-examples/vimium,mrmr1993/vimium,gdh1995/vimium,mrmr1993/vimium,gdh1995/vimium,decaffeinate-examples/vimium,smblott-github/vimium,decaffeinate-examples/vimium,smblott-github/vimium,philc/vimium,philc/vimium,poacher2k/vimium,gdh1995/vimium,smblott-github/vimium