Implement leaning mark mechanism for F, L, P, b, d, h, k, p, q, r to get better mark placement. Now, "narrow" marks will align to these letters' extension parts (#1851).

font-src/support/utils.mjs

@@ -80,3 +80,39 @@ export class $NamedParameterPair$ {
 		this.right = r;
 	}
 }
+
+///////////////////////////////////////////////////////////////////////////////////////////////////
+
+export const MatchUtil = {
+	never() {
+		return false;
+	},
+	equal(x) {
+		return y => y === x;
+	},
+	negate(f) {
+		return x => !f(x);
+	},
+	both(a, b) {
+		return x => a(x) && b(x);
+	},
+	either(a, b) {
+		return x => a(x) || b(x);
+	}
+};
+export function constant(x) {
+	return () => x;
+}
+
+///////////////////////////////////////////////////////////////////////////////////////////////////
+
+export const ArrayUtil = {
+	mapIndexToItems(a, indexes) {
+		let answer = [];
+		for (const item of indexes) answer.push(a[item]);
+		return answer;
+	},
+	insertSliceAt(a, i, b) {
+		a.splice(i, 0, ...b);
+	}
+};