Fix debugger crash inspecting freed object.
Fix debugger crash inspecting freed object.

This seems to be the correct way to validate a reference.
Why is cast_to failing? Is this the correct way of checking if the
object is valid?

Valentactive/godot,ZuBsPaCe/godot,vkbsb/godot,Paulloz/godot,Shockblast/godot,pkowal1982/godot,pkowal1982/godot,josempans/godot,Shockblast/godot,MarianoGnu/godot,BastiaanOlij/godot,akien-mga/godot,BastiaanOlij/godot,vkbsb/godot,Valentactive/godot,Paulloz/godot,Valentactive/godot,josempans/godot,Faless/godot,MarianoGnu/godot,firefly2442/godot,sanikoyes/godot,guilhermefelipecgs/godot,DmitriySalnikov/godot,BastiaanOlij/godot,DmitriySalnikov/godot,DmitriySalnikov/godot,godotengine/godot,Shockblast/godot,akien-mga/godot,Shockblast/godot,ZuBsPaCe/godot,akien-mga/godot,Faless/godot,akien-mga/godot,guilhermefelipecgs/godot,pkowal1982/godot,sanikoyes/godot,Shockblast/godot,sanikoyes/godot,godotengine/godot,MarianoGnu/godot,guilhermefelipecgs/godot,guilhermefelipecgs/godot,ZuBsPaCe/godot,pkowal1982/godot,honix/godot,Zylann/godot,Faless/godot,Paulloz/godot,guilhermefelipecgs/godot,MarianoGnu/godot,Valentactive/godot,sanikoyes/godot,ZuBsPaCe/godot,BastiaanOlij/godot,akien-mga/godot,honix/godot,ZuBsPaCe/godot,godotengine/godot,firefly2442/godot,vnen/godot,Valentactive/godot,sanikoyes/godot,godotengine/godot,honix/godot,Paulloz/godot,vkbsb/godot,pkowal1982/godot,Zylann/godot,BastiaanOlij/godot,godotengine/godot,pkowal1982/godot,MarianoGnu/godot,vkbsb/godot,ZuBsPaCe/godot,firefly2442/godot,sanikoyes/godot,Faless/godot,honix/godot,Faless/godot,vnen/godot,vnen/godot,josempans/godot,Shockblast/godot,Zylann/godot,DmitriySalnikov/godot,MarianoGnu/godot,honix/godot,sanikoyes/godot,pkowal1982/godot,godotengine/godot,firefly2442/godot,Valentactive/godot,DmitriySalnikov/godot,josempans/godot,Zylann/godot,BastiaanOlij/godot,ZuBsPaCe/godot,vnen/godot,vnen/godot,Paulloz/godot,firefly2442/godot,guilhermefelipecgs/godot,BastiaanOlij/godot,Zylann/godot,MarianoGnu/godot,Faless/godot,sanikoyes/godot,Zylann/godot,Shockblast/godot,Paulloz/godot,josempans/godot,akien-mga/godot,Shockblast/godot,guilhermefelipecgs/godot,Valentactive/godot,firefly2442/godot,vkbsb/godot,DmitriySalnikov/godot,ZuBsPaCe/godot,Zylann/godot,vkbsb/godot,MarianoGnu/godot,akien-mga/godot,vnen/godot,josempans/godot,vkbsb/godot,Zylann/godot,DmitriySalnikov/godot,akien-mga/godot,Valentactive/godot,godotengine/godot,pkowal1982/godot,vnen/godot,Faless/godot,vkbsb/godot,josempans/godot,godotengine/godot,BastiaanOlij/godot,firefly2442/godot,Faless/godot,honix/godot,Paulloz/godot,guilhermefelipecgs/godot,firefly2442/godot,josempans/godot,vnen/godot