[TYPO3-core] RFC: #11265: function getTreeList() doesn't use the caching framework

[Rupert Germann]

hi,

Rupert Germann wrote:
> I opt for simply using flush() because I
> a) have no idea yet how to realize the needed functionality in the other
> cache backEnds. and
> b) I doubt that it has a big effect in realworld scenarios.

here's a patch using flush() in all cases where flushByTags() wouldn't help.
Additionally I removed the removeExpiredCacheEntries() function from class
tx_cms_treelistCacheUpdate because it is not used anymore (treelist cache
entries dont expire - they are only cleaned manually by BE actions or by
clearAllCaches)
formerly removeExpiredCacheEntries() was only used in the case that the
expire time was set by an action from class tx_cms_treelistCacheUpdate - is
was not set at insert.

greets
rupert