all: remove exported Decode methods on operations

Add decode functions to the packages that need them instead. For
TransformOp that is used in multiple packages, add the decode
function to the internal ops package.

Signed-off-by: Elias Naur <mail@eliasnaur.com>

ui/app/internal/input/key.go

@@ -97,8 +97,7 @@ loop:
 	for encOp, ok := q.reader.Decode(); ok; encOp, ok = q.reader.Decode() {
 		switch opconst.OpType(encOp.Data[0]) {
 		case opconst.TypeKeyHandler:
-			var op key.HandlerOp
-			op.Decode(encOp.Data, encOp.Refs)
+			op := decodeKeyHandlerOp(encOp.Data, encOp.Refs)
 			var newPri listenerPriority
 			switch {
 			case op.Focus:
@@ -139,3 +138,13 @@ func (p listenerPriority) replaces(p2 listenerPriority) bool {
 	// Favor earliest default focus or latest requested focus.
 	return p > p2 || p == p2 && p == priNewFocus
 }
+
+func decodeKeyHandlerOp(d []byte, refs []interface{}) key.HandlerOp {
+	if opconst.OpType(d[0]) != opconst.TypeKeyHandler {
+		panic("invalid op")
+	}
+	return key.HandlerOp{
+		Focus: d[1] != 0,
+		Key:   refs[0].(input.Key),
+	}
+}