Chore: Remove unused code in legacydata package (#88772)

pkg/tsdb/graphite/graphite.go

@@ -26,7 +26,6 @@ import (
 	"github.com/grafana/grafana/pkg/infra/log"
 	"github.com/grafana/grafana/pkg/infra/tracing"
 	"github.com/grafana/grafana/pkg/setting"
-	"github.com/grafana/grafana/pkg/tsdb/legacydata"
 )
 
 var logger = log.New("tsdb.graphite")
@@ -351,7 +350,7 @@ func epochMStoGraphiteTime(tr backend.TimeRange) (string, string) {
 /**
  * Graphite should always return timestamp as a number but values might be nil when data is missing
  */
-func parseDataTimePoint(dataTimePoint legacydata.DataTimePoint) (time.Time, *float64, error) {
+func parseDataTimePoint(dataTimePoint DataTimePoint) (time.Time, *float64, error) {
 	if !dataTimePoint[1].Valid {
 		return time.Time{}, nil, errors.New("failed to parse data point timestamp")
 	}

pkg/tsdb/graphite/types.go

@@ -1,10 +1,15 @@
 package graphite
 
-import "github.com/grafana/grafana/pkg/tsdb/legacydata"
+import (
+	"github.com/grafana/grafana/pkg/components/null"
+)
 
 type TargetResponseDTO struct {
-	Target     string                          `json:"target"`
-	DataPoints legacydata.DataTimeSeriesPoints `json:"datapoints"`
+	Target     string               `json:"target"`
+	DataPoints DataTimeSeriesPoints `json:"datapoints"`
 	// Graphite <=1.1.7 may return some tags as numbers requiring extra conversion. See https://github.com/grafana/grafana/issues/37614
 	Tags map[string]any `json:"tags"`
 }
+
+type DataTimePoint [2]null.Float
+type DataTimeSeriesPoints []DataTimePoint