We do not use it in this case.

quartz/vmr9: Do not clear the previous allocator and presenter in IVMRFilterConfig9::SetRenderingMode().

There cannot be any previous allocator and presenter. They can only be set by
this function, which cannot be called more than once, or by
IVMRSurfaceAllocatorNotify9::AdviseSurfaceAllocator(), which can only be called
after setting the rendering mode.

Signed-off-by: Eric Pouech <eric.pouech@gmail.com>

Note: it's anyway wrong to search source files inside modules' path
(a proper fix will require revisiting source file handling).
This fix will actually be sufficient when running wine from within
its build tree.
Signed-off-by: Eric Pouech <eric.pouech@gmail.com>

Anyway, it's a pain that we have to maintain two MS symbols
demanglers (this one and the one in dlls/msvcrt).
Signed-off-by: Eric Pouech <epouech@codeweavers.com>

From the tests it behaves more like a semaphore than like an event.

I'm not testing explicitly because I'm not sure it's relevant, but
another indication is that calling ReleaseSemaphore() returns
ERROR_ACCESS_DENIED, while calling SetEvent() returns
ERROR_INVALID_HANDLE.