1822200 - [meta] Remove special case code for Android API levels < 21 (Lollipop 5.0)

Status: NEW

(GeckoView :: General, task, P3)

Description

[Chris Peterson [:cpeterson]]

SDK_INT checks for API levels <= 21:
https://searchfox.org/mozilla-central/search?q=SDK_INT.%2B%281%5Cd%7C2%5B01%5D%29&path=mobile%2Fandroid%2Fgeckoview&case=true&regexp=true

Special case for User-Agent strong on Android versions < 4.4:
https://searchfox.org/mozilla-central/rev/2ede53e39955988f98db4369f7ce09614b22104a/netwerk/protocol/http/nsHttpHandler.cpp#885-890

Some test code that checks for old Android versions:
https://searchfox.org/mozilla-central/search?q=androidVersion&path=test&case=false&regexp=false