Let queue_free() work on nodes which are not in the scene tree
Let queue_free() work on nodes which are not in the scene tree

In practice such nodes could directly be free()'ed, but this little change
prevents users from leaking memory by mistake.
Closes #9074.

pkowal1982/godot,RandomShaper/godot,akien-mga/godot,pkowal1982/godot,Brickcaster/godot,RandomShaper/godot,guilhermefelipecgs/godot,MarianoGnu/godot,RandomShaper/godot,akien-mga/godot,pkowal1982/godot,ageazrael/godot,firefly2442/godot,Paulloz/godot,Paulloz/godot,jejung/godot,BastiaanOlij/godot,BastiaanOlij/godot,pkowal1982/godot,ZuBsPaCe/godot,mcanders/godot,MarianoGnu/godot,Faless/godot,Valentactive/godot,zicklag/godot,godotengine/godot,jejung/godot,Valentactive/godot,ex/godot,DmitriySalnikov/godot,Faless/godot,mcanders/godot,godotengine/godot,guilhermefelipecgs/godot,okamstudio/godot,pkowal1982/godot,sanikoyes/godot,MarianoGnu/godot,Faless/godot,josempans/godot,guilhermefelipecgs/godot,groud/godot,Zylann/godot,Brickcaster/godot,Shockblast/godot,RandomShaper/godot,FateAce/godot,ex/godot,NateWardawg/godot,sanikoyes/godot,firefly2442/godot,firefly2442/godot,NateWardawg/godot,Zylann/godot,Valentactive/godot,n-pigeon/godot,Shockblast/godot,NateWardawg/godot,Shockblast/godot,MarianoGnu/godot,groud/godot,godotengine/godot,okamstudio/godot,vnen/godot,Paulloz/godot,Zylann/godot,guilhermefelipecgs/godot,Faless/godot,vnen/godot,pkowal1982/godot,firefly2442/godot,n-pigeon/godot,zicklag/godot,ex/godot,MarianoGnu/godot,josempans/godot,okamstudio/godot,akien-mga/godot,vnen/godot,zicklag/godot,FateAce/godot,n-pigeon/godot,groud/godot,mcanders/godot,Zylann/godot,Valentactive/godot,Zylann/godot,ex/godot,ageazrael/godot,Brickcaster/godot,RandomShaper/godot,mcanders/godot,MarianoGnu/godot,godotengine/godot,n-pigeon/godot,sanikoyes/godot,ageazrael/godot,Paulloz/godot,NateWardawg/godot,NateWardawg/godot,vkbsb/godot,akien-mga/godot,vnen/godot,Paulloz/godot,DmitriySalnikov/godot,ZuBsPaCe/godot,mcanders/godot,n-pigeon/godot,akien-mga/godot,josempans/godot,honix/godot,NateWardawg/godot,ZuBsPaCe/godot,ZuBsPaCe/godot,Valentactive/godot,sanikoyes/godot,Zylann/godot,firefly2442/godot,okamstudio/godot,jejung/godot,mcanders/godot,guilhermefelipecgs/godot,ZuBsPaCe/godot,okamstudio/godot,n-pigeon/godot,DmitriySalnikov/godot,ex/godot,Brickcaster/godot,zicklag/godot,firefly2442/godot,ZuBsPaCe/godot,vnen/godot,Zylann/godot,guilhermefelipecgs/godot,honix/godot,sanikoyes/godot,NateWardawg/godot,Shockblast/godot,firefly2442/godot,Valentactive/godot,MarianoGnu/godot,okamstudio/godot,vkbsb/godot,godotengine/godot,vnen/godot,ex/godot,guilhermefelipecgs/godot,honix/godot,groud/godot,Valentactive/godot,ex/godot,pkowal1982/godot,n-pigeon/godot,Paulloz/godot,BastiaanOlij/godot,vkbsb/godot,zicklag/godot,Shockblast/godot,Shockblast/godot,DmitriySalnikov/godot,Faless/godot,groud/godot,vkbsb/godot,Brickcaster/godot,josempans/godot,Brickcaster/godot,BastiaanOlij/godot,sanikoyes/godot,ageazrael/godot,vnen/godot,BastiaanOlij/godot,guilhermefelipecgs/godot,ZuBsPaCe/godot,jejung/godot,akien-mga/godot,ageazrael/godot,FateAce/godot,DmitriySalnikov/godot,okamstudio/godot,sanikoyes/godot,DmitriySalnikov/godot,pkowal1982/godot,RandomShaper/godot,honix/godot,okamstudio/godot,jejung/godot,sanikoyes/godot,Shockblast/godot,josempans/godot,firefly2442/godot,okamstudio/godot,vnen/godot,godotengine/godot,Shockblast/godot,Valentactive/godot,Zylann/godot,Brickcaster/godot,ageazrael/godot,ageazrael/godot,groud/godot,DmitriySalnikov/godot,akien-mga/godot,BastiaanOlij/godot,NateWardawg/godot,Paulloz/godot,RandomShaper/godot,BastiaanOlij/godot,godotengine/godot,BastiaanOlij/godot,okamstudio/godot,ZuBsPaCe/godot,vkbsb/godot,NateWardawg/godot,FateAce/godot,jejung/godot,honix/godot,josempans/godot,akien-mga/godot,godotengine/godot,Faless/godot,FateAce/godot,Faless/godot,FateAce/godot,josempans/godot,vkbsb/godot,Faless/godot,josempans/godot,honix/godot,zicklag/godot,vkbsb/godot,vkbsb/godot,ex/godot,MarianoGnu/godot