[glyf] Return component transform as part of control data

This makes sure that when we are building variable fonts, we
check that all masters have the same component transform in
composite glyphs.  We were not checking for this before.

Lib/fontTools/ttLib/tables/_g_l_y_f.py

@@ -377,7 +377,7 @@ class table__g_l_y_f(DefaultTable.DefaultTable):
 				numberOfContours=glyph.numberOfContours,
 				endPts=list(range(len(glyph.components))),
 				flags=None,
-				components=[c.glyphName for c in glyph.components],
+				components=[(c.glyphName, getattr(c, 'transform', None)) for c in glyph.components],
 			)
 		else:
 			coords, endPts, flags = glyph.getCoordinates(self)