[TYPO3-core] RFX: #9286: use native JSON-methods instead of 3rd party json script

[Benjamin Mack]

Hey Masi and Dmitry,

actually, that was me that introduced the "policy". That was more a 
@deprecated part of the file / function stating that it will be removed 
two major versions later. Well, as we mark the JSON script as deprecated 
in 4.3, we can remove it in 4.5, if that's ok with you guys. However, we 
should add this in the patch of the RFC.
A public statement in the dev-news would be good as well, once we commit 
that thing.

btw: that's the nice thing about the t3lib_div wrapper: Everybody should 
use this function anyway, so we people don't need to change their 
scripts. I remember using JSON through the t3lib_div class but not by 
instantiating the class by myself, so we "should" be good to go.

-- 
All the best,
benni.
-SDG-