Fix bugs in ingester iterators.

Signed-off-by: Tom Wilkie <tom.wilkie@gmail.com>

pkg/ingester/chunk.go

@@ -61,6 +61,7 @@ type dumbChunkIterator struct {
 }
 
 func (i *dumbChunkIterator) Next() bool {
+	i.i++
 	return i.i < len(i.entries)
 }
 

pkg/querier/http.go

@@ -75,7 +75,7 @@ func ReadBatch(i EntryIterator, size int) (*logproto.QueryResponse, error) {
 	}
 
 	result := logproto.QueryResponse{
-		Streams: make([]*logproto.Stream, len(streams)),
+		Streams: make([]*logproto.Stream, 0, len(streams)),
 	}
 	for _, stream := range streams {
 		result.Streams = append(result.Streams, stream)