[Discover] Remove redundant execution of onRequestStart when fetching…

… data (#94093)

src/plugins/discover/public/application/angular/discover.js

@@ -700,7 +700,13 @@ function discoverController($route, $scope, Promise) {
 
   async function setupVisualization() {
     // If no timefield has been specified we don't create a histogram of messages
-    if (!getTimeField() || $scope.state.hideChart) return;
+    if (!getTimeField() || $scope.state.hideChart) {
+      if ($scope.volatileSearchSource.getField('aggs')) {
+        // cleanup aggs field in case it was set before
+        $scope.volatileSearchSource.removeField('aggs');
+      }
+      return;
+    }
     const { interval: histogramInterval } = $scope.state;
 
     const visStateAggs = [
@@ -723,11 +729,6 @@ function discoverController($route, $scope, Promise) {
       visStateAggs
     );
 
-    $scope.volatileSearchSource.onRequestStart((searchSource, options) => {
-      if (!$scope.opts.chartAggConfigs) return;
-      return $scope.opts.chartAggConfigs.onSearchRequestStart(searchSource, options);
-    });
-
     $scope.volatileSearchSource.setField('aggs', function () {
       if (!$scope.opts.chartAggConfigs) return;
       return $scope.opts.chartAggConfigs.toDsl();