Right now, this component is a copy/paste from Debug, but it can and should diverge now.

Here are things that should be done, to be confirmed by trying:

• remove ExceptionHandler: we don't need anymore to recover from failed userland rendering ([ErrorHandler] Decouple from ErrorRenderer component #32637)
• remove the FatalErrorException class and namespace: this doesn't apply anymore since PHP7, right? ([ErrorHandler] Rework fatal errors #33053)
• add type declarations ([ErrorHandler] Added type declarations where possible #32812)
• support Throwable directly ([ErrorHandler] Forward \Throwable #33038)
• decouple from the ErrorRenderer component ([ErrorHandler] Decouple from ErrorRenderer component #32637)

/cc @fancyweb @yceruto as you like this part of the code base :)