fix(core): reset the count before resetting BufferObject to avoid lock count...

fix(core): reset the count before resetting BufferObject to avoid lock count assert at buffer destruction

Resetting the counter in the destructor **BEFORE** resetting BufferObject shared pointer is required ! Otherwise, the lock count assert in the destruction of the buffer, in `BufferManager::::unregisterBufferImpl()` will be triggered.

Also remove hack in SDistorsion service.

Closes #796
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