TLS v1.2 support on Webview Android

I faced with one big problem: built-in browser (WebView), what we use for authentication, supports TLS 1.1+ only from 4.4 KitKat. Android OS supports TLS 1.1+ from 16 API version, but WebView supports TLS 1.1+ only from 19 API version. I didn’t find opportunity to set TLS protocol to WebView manually. So we can’t login in system through web on devices below KItKat. I checked this on real devices Samsung 4.1.2 and Asus 4.2.2 , and emulator 4.3.1