rpc: remove HexNumber, replace all uses with hexutil types

This change couldn't be automated because HexNumber was used for numbers
of all sizes.

rpc/types.go

@@ -121,91 +121,6 @@ type ServerCodec interface {
 	Closed() <-chan interface{}
 }
 
-// HexNumber serializes a number to hex format using the "%#x" format
-type HexNumber big.Int
-
-// NewHexNumber creates a new hex number instance which will serialize the given val with `%#x` on marshal.
-func NewHexNumber(val interface{}) *HexNumber {
-	if val == nil {
-		return nil // note, this doesn't catch nil pointers, only passing nil directly!
-	}
-
-	if v, ok := val.(*big.Int); ok {
-		if v != nil {
-			return (*HexNumber)(new(big.Int).Set(v))
-		}
-		return nil
-	}
-
-	rval := reflect.ValueOf(val)
-
-	var unsigned uint64
-	utype := reflect.TypeOf(unsigned)
-	if t := rval.Type(); t.ConvertibleTo(utype) {
-		hn := new(big.Int).SetUint64(rval.Convert(utype).Uint())
-		return (*HexNumber)(hn)
-	}
-
-	var signed int64
-	stype := reflect.TypeOf(signed)
-	if t := rval.Type(); t.ConvertibleTo(stype) {
-		hn := new(big.Int).SetInt64(rval.Convert(stype).Int())
-		return (*HexNumber)(hn)
-	}
-
-	return nil
-}
-
-func (h *HexNumber) UnmarshalJSON(input []byte) error {
-	length := len(input)
-	if length >= 2 && input[0] == '"' && input[length-1] == '"' {
-		input = input[1 : length-1]
-	}
-
-	hn := (*big.Int)(h)
-	if _, ok := hn.SetString(string(input), 0); ok {
-		return nil
-	}
-
-	return fmt.Errorf("Unable to parse number")
-}
-
-// MarshalJSON serialize the hex number instance to a hex representation.
-func (h *HexNumber) MarshalJSON() ([]byte, error) {
-	if h != nil {
-		hn := (*big.Int)(h)
-		if hn.BitLen() == 0 {
-			return []byte(`"0x0"`), nil
-		}
-		return []byte(fmt.Sprintf(`"0x%x"`, hn)), nil
-	}
-	return nil, nil
-}
-
-func (h *HexNumber) Int() int {
-	hn := (*big.Int)(h)
-	return int(hn.Int64())
-}
-
-func (h *HexNumber) Int64() int64 {
-	hn := (*big.Int)(h)
-	return hn.Int64()
-}
-
-func (h *HexNumber) Uint() uint {
-	hn := (*big.Int)(h)
-	return uint(hn.Uint64())
-}
-
-func (h *HexNumber) Uint64() uint64 {
-	hn := (*big.Int)(h)
-	return hn.Uint64()
-}
-
-func (h *HexNumber) BigInt() *big.Int {
-	return (*big.Int)(h)
-}
-
 var (
 	pendingBlockNumber  = big.NewInt(-2)
 	latestBlockNumber   = big.NewInt(-1)