Don't force fromlevelselect to be false after a pre-map cutscene

It turns out that the mechanism to keep emeralds after warping to a map is kinda hacky, relying on the fromlevelselect or FLS parameter. More specifically, even if resetplayer is true, FLS being true will cause emeralds to be kept upon warping.

However, in the case of a pre-map cutscene, the value of FLS was not stored. Instead, a cutscene ending would call a map change with the FLS parameter always being false. This branch changes that call to use the value of FLS from before the cutscene.

This system could use a proper rewrite, but for now this fixes #1003 (closed).