Model IEventProcessor acquire/release exactly after XInterface

...so classes deriving from both can easily share a single implementation for
these functions.

Change-Id: I6882dddc8b3ea3b0192d85102a0305494d964dc1
More compat stuff

(currently only used by a not-yet committed plugin, though)

Change-Id: Id62ea41031ad8ba4495ef46877ad7a10bc58fb05
Skip gcj's gij executable, like other JREs' java executables

Change-Id: Ida84a271a066e89ceb7e5dd2fd23a744f5529917
Don't Valgrind into java children in unit tests

...similarly to desktop/scripts/soffice.sh preventing that for LO itself.

One problem is that, even if it does not find any errors, Valgrind writes onto
a traced child's stderr, and when jvmfwk searches for a JRE to use, it takes
output to stderr into account, so would start to behave differently when run
under Valgrind.

--trace-children-skip appears to be new since Valgrind 3.6, and older versions
would probably fail early when they see this unknown-to-them option.  If this
turns out to be a problem in practice (current version is 3.9), we probably need
to make this conditional on a configure.ac check.

Change-Id: Ia6a72bdcd666d68ed0539170f3fc476292e82b96
Fix races in AsyncEventNotifier::execute

* m_aDeadProcessors was useless; for one, removeEventsForProcessor could never
  have run (and set m_aDeadProcessors) between execute's reading from aEvents
  and checking m_aDeadProcessors (because of the use of aMutex in both
  functions), and if that were addressed, there would always be a race that
  execute would run a processor that has just been removed.  Clients have to be
  aware that a call to removeEventsForProcessor is just an optimization hint,
  but does not guarantee that the given processor is not called from the execute
  thread after removeEventsForProcessor returns.

* The sequence

    aGuard.clear(); aPendingActions.reset(); aPanedingActions.wait();

  could cause calls to aPendingActions.set() to get lost, both for signalling
  new content in the queue and for signalling termination.

Change-Id: I43293e3d5090c2d46db8bc8ed6fb9c71e049d55c