Fix [#28195] Particles objects disappear in viewport, and 90° rotation

Reported by Jean Francois Sarazin

Lack of normal normalisation caused scaling issues. SIGGRAPH fix by jahka and jesterKing. Thanks to host dfelinto with entertainment provided by slikdigit.

source/blender/blenkernel/intern/particle.c

@@ -4389,6 +4389,7 @@ void psys_get_dupli_path_transform(ParticleSimulationData *sim, ParticleData *pa
 	copy_m3_m4(nmat, ob->imat);
 	transpose_m3(nmat);
 	mul_m3_v3(nmat, nor);
+	normalize_v3(nor);
 
 	/* make sure that we get a proper side vector */
 	if(fabs(dot_v3v3(nor,vec))>0.999999) {