short-circuit redraw for spike attribute relayouts

Author: alexcjohnson

src/plot_api/plot_api.js

@@ -2124,14 +2124,16 @@ function _relayout(gd, aobj) {
                 flags.doticks = flags.dolayoutstyle = true;
             }
             /*
-             * hovermode and dragmode don't need any redrawing, since they just
-             * affect reaction to user input, everything else, assume full replot.
+             * hovermode, dragmode, and spikes don't need any redrawing, since they just
+             * affect reaction to user input. Everything else, assume full replot.
              * height, width, autosize get dealt with below. Except for the case of
              * of subplots - scenes - which require scene.updateFx to be called.
              */
-            else if(['hovermode', 'dragmode'].indexOf(ai) !== -1) flags.domodebar = true;
-            else if(['hovermode', 'dragmode', 'height',
-                'width', 'autosize'].indexOf(ai) === -1) {
+            else if(['hovermode', 'dragmode'].indexOf(ai) !== -1 ||
+                    ai.indexOf('spike') !== -1) {
+                flags.domodebar = true;
+            }
+            else if(['height', 'width', 'autosize'].indexOf(ai) === -1) {
                 flags.doplot = true;
             }