Slice level cache_timeout isn't taken into consideration (#2631)

superset/assets/javascripts/explorev2/stores/controls.jsx

@@ -1199,5 +1199,12 @@ export const controls = {
     hidden: true,
     description: 'The id of the active slice',
   },
+
+  cache_timeout: {
+    type: 'HiddenControl',
+    label: 'Cache Timeout (seconds)',
+    hidden: true,
+    description: 'The number of seconds before expiring the cache',
+  },
 };
 export default controls;

superset/assets/javascripts/explorev2/stores/visTypes.js

@@ -12,7 +12,7 @@ export const sections = {
     controlSetRows: [
       ['datasource'],
       ['viz_type'],
-      ['slice_id'],
+      ['slice_id', 'cache_timeout'],
     ],
   },
   sqlaTimeSeries: {