Tweak ligature component matching for ligature formation If two marks want to ligate and they belong to different components of the same ligature glyph, and said ligature glyph is to be ignored according to mark-filtering rules, then allow. Example Burmese senquence: U+1004,U+103A,U+1039,U+101B,U+103D,U+102D Test font provided by Norbert Lindenberg. Fixes https://github.com/behdad/harfbuzz/issues/545