[subset] prevent CPAL nameIDs from being dropped

Lib/fontTools/subset/__init__.py

@@ -2553,6 +2553,10 @@ def prune_pre_subset(self, font, options):
 		if stat.table.AxisValueArray:
 			nameIDs.update([val_rec.ValueNameID for val_rec in stat.table.AxisValueArray.AxisValue])
 		nameIDs.update([axis_rec.AxisNameID for axis_rec in stat.table.DesignAxisRecord.Axis])
+	cpal = font.get('CPAL')
+	if cpal and cpal.version == 1:
+		nameIDs.update(cpal.paletteLabels)
+		nameIDs.update(cpal.paletteEntryLabels)
 	if '*' not in options.name_IDs:
 		self.names = [n for n in self.names if n.nameID in nameIDs]
 	if not options.name_legacy:

Tests/subset/subset_test.py

@@ -1359,8 +1359,6 @@ def test_subset_COLRv1_and_CPALv1(colrv1_cpalv1_path):
     assert "CPAL" in subset_font
     cpal = subset_font["CPAL"]
     name_table = subset_font["name"]
-    import pdb
-    pdb.set_trace()
     assert [name_table.getDebugName(name_id) for name_id in cpal.paletteEntryLabels] == [
         # "first color",  # The first color was pruned
         "second color",