Revert "removes save dialog"

This reverts commit 14e89ff.

Author: dxenes1

src/neuroglancer/graph/path_finder_state.ts

@@ -206,6 +206,35 @@ class PathBetweenSupervoxels extends RefCounted {
     this.addSourceOrTarget(newTarget);
   }
 
+  getLatestSegments(layer: SegmentationUserLayerWithGraph) {
+    if (!this._source || !this._target){
+      return
+    }
+    const {segmentSelectionState} = layer.displayState;
+    const newSource: Point = {
+      id: '',
+      segments: [
+        segmentSelectionState.rawSelectedSegment.clone(),
+        segmentSelectionState.selectedSegment.clone()
+      ],
+      point: this._source.point,
+      type: AnnotationType.POINT,
+    };
+
+    const newTarget: Point = {
+      id: '',
+      segments: [
+        segmentSelectionState.rawSelectedSegment.clone(),
+        segmentSelectionState.selectedSegment.clone()
+      ],
+      point: this._target.point,
+      type: AnnotationType.POINT,
+    };
+    this.clear();
+    this.addSourceOrTarget(newSource);
+    this.addSourceOrTarget(newTarget);
+  }
+
   toJSON() {
     const x: any = {
       [ANNOTATION_PATH_JSON_KEY]: this.annotationSource.toJSON(),