[TASK] Consistently retrieve ApplicationContext from GeneralUtility

As documented in Bootstrap code, GeneralUtility should be
used instead of Bootstrap to retrieve the ApplicationContext.

Therefore ClassLoadingInformation is adapted to read the
ApplicationContext from GeneralUtility. Bootstrap now pushes the
ApplicationContext early to GeneralUtility to be available for
ClassLoadingInformation during bootstrap.

Change-Id: I119ac944dd49c7d063b0f1e05f23e48f664ce2bc
Releases: master
Resolves: #84083
Reviewed-on: https://review.typo3.org/55940


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Frank Naegler <frank.naegler@typo3.org>
Tested-by: Frank Naegler <frank.naegler@typo3.org>
Reviewed-by: Christian Kuhn <lolli@schwarzbu.ch>
Tested-by: Christian Kuhn <lolli@schwarzbu.ch>