FileBasedWebSessionCacheCleaner: Make CleanupTask a static inner class

I'm not sure what the reason was for defining the CleanupTask
class as a separate class outside of the main class in the file,
but it's unusual to do this rather than making it a static inner
class.

Reported-By: Martin Fick <mfick@codeaurora.org>
Change-Id: I975368fb20533a62eb8fe936a8c345371ea11f3b
2 files changed