Only run emptyCategories loop when restyle or relayout calc flag is true

Author: wbrgss

src/plot_api/plot_api.js

@@ -2737,16 +2737,6 @@ function react(gd, data, layout, config) {
 
         applyUIRevisions(gd.data, gd.layout, oldFullData, oldFullLayout);
 
-        var allNames = Object.getOwnPropertyNames(oldFullLayout);
-        for(var q = 0; q < allNames.length; q++) {
-            var name = allNames[q];
-            var start = name.substring(0, 5);
-            if(start === 'xaxis' || start === 'yaxis') {
-                var emptyCategories = oldFullLayout[name]._emptyCategories;
-                if(emptyCategories) emptyCategories();
-            }
-        }
-
         // "true" skips updating calcdata and remapping arrays from calcTransforms,
         // which supplyDefaults usually does at the end, but we may need to NOT do
         // if the diff (which we haven't determined yet) says we'll recalc
@@ -2772,10 +2762,22 @@ function react(gd, data, layout, config) {
 
         if(updateAutosize(gd)) relayoutFlags.layoutReplot = true;
 
-        // clear calcdata if required
-        if(restyleFlags.calc || relayoutFlags.calc) gd.calcdata = undefined;
+        // clear calcdata and empty categories if required
+        if(restyleFlags.calc || relayoutFlags.calc) {
+            gd.calcdata = undefined;
+            var allNames = Object.getOwnPropertyNames(newFullLayout);
+            for(var q = 0; q < allNames.length; q++) {
+                var name = allNames[q];
+                var start = name.substring(0, 5);
+                if(start === 'xaxis' || start === 'yaxis') {
+                    var emptyCategories = newFullLayout[name]._emptyCategories;
+                    if(emptyCategories) emptyCategories();
+                }
+            }
         // otherwise do the calcdata updates and calcTransform array remaps that we skipped earlier
-        else Plots.supplyDefaultsUpdateCalc(gd.calcdata, newFullData);
+        } else {
+            Plots.supplyDefaultsUpdateCalc(gd.calcdata, newFullData);
+        }
 
         // Note: what restyle/relayout use impliedEdits and clearAxisTypes for
         // must be handled by the user when using Plotly.react.