measurements: keep tree strain colors regardless of visibility

We need the tree strain colors for all strains regardless of visibility
so that we can display the colors for the reference strains in the
y-axis label even when the strain is not visible in the tree.

src/components/measurements/index.js

@@ -65,25 +65,22 @@ const treeStrainPropertySelector = (state) => {
     // Only store properties of terminal strain nodes
     if (!node.hasChildren) {
       treeStrainVisibility[node.name] = tree.visibility[index];
-      // Only store colors for visible strains since only measurmeents
-      // for visible strains will be displayed
-      if (isVisible(tree.visibility[index])) {
-        /*
-        * If the color scale is continuous, we want to group by the legend value
-        * instead of the specific strain attribute in order to combine all values
-        * within the legend bounds into a single group.
-        */
-        let attribute = getTipColorAttribute(node, colorScale);
-        if (colorScale.continuous) {
-          const matchingLegendValue = colorScale.visibleLegendValues
-            .find((legendValue) => determineLegendMatch(legendValue, node, colorScale));
-          if (matchingLegendValue !== undefined) attribute = matchingLegendValue;
-        }
-        treeStrainColors[node.name] = {
-          attribute,
-          color: tree.nodeColors[index]
-        };
+      /*
+      * If the color scale is continuous, we want to group by the legend value
+      * instead of the specific strain attribute in order to combine all values
+      * within the legend bounds into a single group.
+      */
+      let attribute = getTipColorAttribute(node, colorScale);
+      if (colorScale.continuous) {
+        const matchingLegendValue = colorScale.visibleLegendValues
+          .find((legendValue) => determineLegendMatch(legendValue, node, colorScale));
+        if (matchingLegendValue !== undefined) attribute = matchingLegendValue;
       }
+      treeStrainColors[node.name] = {
+        attribute,
+        color: tree.nodeColors[index]
+      };
+
     }
     return treeStrainProperty;
   }, intitialTreeStrainProperty);