Otherwise if you happen to compile vcl/source/app/svmain.cxx with
OSL_DEBUG_LEVEL > 0 but not this file, you get an undefined symbol
DebugEventInjector::getCreate().

In general I think our intent is that ideally it should be possible to
compile an arbitrary selection of source files with OSL_DEBUG_LEVEL=0,
and others with OSL_DEBUG_LEVEL=1. (For debugging functionality that
does require consistency across the codebase, we have DBG_UTIL.)

Note that DebugEventInjector::getCreate() will be called from
InitVCL() only when svmain.cxx is compiled with OSL_DEBUG_LEVEL > 0,
though. So for a "production" build with no debug compilation, this
change has no run-time effect.

Change-Id: I3411edfbbbaae21561363634e5eec5ac0cf53418
Reviewed-on: https://gerrit.libreoffice.org/71757
Tested-by: Jenkins
Reviewed-by: Tor Lillqvist <tml@collabora.com>