The WebView shipped with Android 4.4 (KitKat) is based on the same code as Chrome for Android version 30. This WebView does not have full feature parity with Chrome for Android and is given the version number 184.108.40.206.
The updated WebView shipped with Android 4.4.3 has the version number 220.127.116.11.
A developer preview WebView is shipping with the Android L Developer Preview. The developer preview version number is 18.104.22.168.
Caution: You cannot publish apps using the L Developer Preview to the Google Play store.
The WebView in Android L can be updated via the Play Store, so you need to check the latest version on the device under App Settings.
... read the whole story at developer.chrome.com.