core, eth, trie: bloom filter for trie node dedup during fast sync (#19489)

* core, eth, trie: bloom filter for trie node dedup during fast sync

* eth/downloader, trie: address review comments

* core, ethdb, trie: restart fast-sync bloom construction now and again

* eth/downloader: initialize fast sync bloom on startup

* eth: reenable eth/62 until we properly remove it

vendor/github.com/steakknife/hamming/hamming.go

@@ -0,0 +1,70 @@
+//
+// Package hamming distance calculations in Go
+//
+// https://github.com/steakknife/hamming
+//
+// Copyright © 2014, 2015, 2016, 2018 Barry Allard
+//
+// MIT license
+//
+package hamming
+
+// Int8 hamming distance of two int8's
+func Int8(x, y int8) int {
+	return CountBitsInt8(x ^ y)
+}
+
+// Int16 hamming distance of two int16's
+func Int16(x, y int16) int {
+	return CountBitsInt16(x ^ y)
+}
+
+// Int32 hamming distance of two int32's
+func Int32(x, y int32) int {
+	return CountBitsInt32(x ^ y)
+}
+
+// Int64 hamming distance of two int64's
+func Int64(x, y int64) int {
+	return CountBitsInt64(x ^ y)
+}
+
+// Int hamming distance of two ints
+func Int(x, y int) int {
+	return CountBitsInt(x ^ y)
+}
+
+// Uint8 hamming distance of two uint8's
+func Uint8(x, y uint8) int {
+	return CountBitsUint8(x ^ y)
+}
+
+// Uint16 hamming distance of two uint16's
+func Uint16(x, y uint16) int {
+	return CountBitsUint16(x ^ y)
+}
+
+// Uint32 hamming distance of two uint32's
+func Uint32(x, y uint32) int {
+	return CountBitsUint32(x ^ y)
+}
+
+// Uint64 hamming distance of two uint64's
+func Uint64(x, y uint64) int {
+	return CountBitsUint64(x ^ y)
+}
+
+// Uint hamming distance of two uint's
+func Uint(x, y uint) int {
+	return CountBitsUint(x ^ y)
+}
+
+// Byte hamming distance of two bytes
+func Byte(x, y byte) int {
+	return CountBitsByte(x ^ y)
+}
+
+// Rune hamming distance of two runes
+func Rune(x, y rune) int {
+	return CountBitsRune(x ^ y)
+}