Cleanup the new ErrorHandler component #32605
Description
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 :)