Language context detection issue with content language

Problem/Motivation

Inconrrect language detected in edit pages with language context.

Steps to reproduce

Make a language detection rule with: Interface text language diff with Content language
in page /admin/config/regional/language/detection

1. add new language "Chinese, Simplified"
2. in Detection and selection page: configure "Selected language" for Interface text language detection and select "Chinese, Simplified"
3. in Detection and selection page: check "Customize Content language detection to differ from Interface text language detection settings"
4. in Detection and selection page: check "Account administration pages" for Interface text language detection and put it first priority
5. in Detection and selection page: check "URL" for Interface text language detection and set prefix "" for "Chinese, Simplified", "en" for "English"
6. in Detection and selection page: check "URL" for Content language detection
7. Set "Administration pages language" with "English" in admin user profile

Proposed resolution

Lanugage context shloud get current language from Content language detection