core, eth, ethdb, trie: simplify range proofs

core/rawdb/table.go

@@ -176,11 +176,6 @@ func (b *tableBatch) Delete(key []byte) error {
 	return b.batch.Delete(append([]byte(b.prefix), key...))
 }
 
-// KeyCount retrieves the number of keys queued up for writing.
-func (b *tableBatch) KeyCount() int {
-	return b.batch.KeyCount()
-}
-
 // ValueSize retrieves the amount of data queued up for writing.
 func (b *tableBatch) ValueSize() int {
 	return b.batch.ValueSize()

core/state/snapshot/generate.go

@@ -368,7 +368,7 @@ func (dl *diskLayer) proveRange(stats *generatorStats, root common.Hash, prefix
 	}
 	// Verify the snapshot segment with range prover, ensure that all flat states
 	// in this range correspond to merkle trie.
-	_, cont, err := trie.VerifyRangeProof(root, origin, last, keys, vals, proof)
+	cont, err := trie.VerifyRangeProof(root, origin, last, keys, vals, proof)
 	return &proofResult{
 			keys:     keys,
 			vals:     vals,