GitLab

https://crrev.com/c/2123311 changes the route for os languages setting
page. This results in the need to:
- Update the hard-coded strings in os_languages_section.html
- Update the constants in system_tray_client
and virtual_keyboard_delegate (found this by doing a codesearch).

Note: chrome::kOsLanguagesDetailsSubPage is equivalent to the old
chrome::kLanguagesSubPage

Bug: 1068045
Change-Id: Ifee9e8ab7fb392787c1a9450a56d5b30b5eff127
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2137105Reviewed-by: James Cook <jamescook@chromium.org>
Reviewed-by: Darren Shen <shend@chromium.org>
Commit-Queue: My Nguyen <myy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#756901}