Fix possible crash when calling Tree.notification from _ready
Fix possible crash when calling Tree.notification from _ready

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