Fix ResolveTypedef result when run before gROOT init.
Fix ResolveTypedef result when run before gROOT init.

Before this commit it was returning a null string for any input, it now return the input unchanged
when it is run before initialization

olifre/root,karies/root,zzxuanyuan/root,zzxuanyuan/root,root-mirror/root,root-mirror/root,olifre/root,karies/root,root-mirror/root,root-mirror/root,olifre/root,zzxuanyuan/root,karies/root,olifre/root,olifre/root,root-mirror/root,karies/root,karies/root,zzxuanyuan/root,zzxuanyuan/root,root-mirror/root,zzxuanyuan/root,zzxuanyuan/root,karies/root,zzxuanyuan/root,olifre/root,zzxuanyuan/root,karies/root,olifre/root,root-mirror/root,root-mirror/root,karies/root,zzxuanyuan/root,olifre/root,zzxuanyuan/root,zzxuanyuan/root,root-mirror/root,olifre/root,root-mirror/root,root-mirror/root,karies/root,karies/root,olifre/root,olifre/root,karies/root