Tweak a few tagcache things.

* Take out pointless dircache_search; nothing can be reconstructed
with the given info in find_entry_ram(); don't even try there.
Path AND index id must be known. Work it out later.

* Timed yield must be far more often than once every 1/4 second (?!)

* Do better the memory-remaining checks for ramcache load.

* Root separator mustn't be doubled up when searching files.

Change-Id: I091813f4495f3bd0d0c4672bc674df52343b3e48
1 file changed