Collect all of the geocoverage for the bundle.

def post_build_geo_coverage(self):
        """Collect all of the geocoverage for the bundle."""

        spaces = set()
        grains = set()

        def resolve(term):
            places = list(self.library.search.search_identifiers(term))

            if not places:
                raise BuildError(
                    "Failed to find space identifier '{}' in full text identifier search".format(term))

            return places[0].vid

        if self.metadata.about.space:  # From the bundle metadata
            spaces.add(resolve(self.metadata.about.space))

        if self.metadata.about.grain:  # From the bundle metadata
            grains.add(self.metadata.about.grain)

        if self.identity.bspace:  # And from the bundle name
            spaces.add(resolve(self.identity.bspace))

        # From all of the partitions
        for p in self.partitions.all:
            if 'geo_coverage' in p.record.data:
                for space in p.record.data['geo_coverage']:
                    spaces.add(space)

            if 'geo_grain' in p.record.data:
                for grain in p.record.data['geo_grain']:
                    grains.add(grain)

        def conv_grain(g):
            """Some grain are expressed as summary level names, not gvids."""
            try:
                c = GVid.get_class(g)
                return b(c().summarize())
            except NotASummaryName:
                return g

        self.metadata.coverage.geo = sorted(spaces)
        self.metadata.coverage.grain = sorted(conv_grain(g) for g in grains)

        self.metadata.write_to_dir()