[Security Solution][THI] - remove obsolete timelineEsqlTabDisabled feature flag (#205175)

## Summary

This PR removes the `timelineEsqlTabDisabled` feature flag that was
introduced a long time ago and has been in `disabled: false` state for
many months.
I noticed that the line was moved in [this
PR](https://github.com/elastic/kibana/pull/176064) over 6 months ago but
the introduction of the feature precedes that.

No UI changes introduced!

x-pack/solutions/security/plugins/security_solution/common/experimental_features.ts

@@ -184,12 +184,6 @@ export const allowedExperimentalValues = Object.freeze({
    */
   jamfDataInAnalyzerEnabled: true,
 
-  /*
-   * Disables discover esql tab within timeline
-   *
-   */
-  timelineEsqlTabDisabled: false,
-
   /**
    * Enables graph visualization in alerts flyout
    */

x-pack/solutions/security/plugins/security_solution/public/assistant/send_to_timeline/index.tsx

@@ -34,7 +34,6 @@ import {
 } from '../../timelines/store/actions';
 import { useDiscoverInTimelineContext } from '../../common/components/discover_in_timeline/use_discover_in_timeline_context';
 import { useShowTimeline } from '../../common/utils/timeline/use_show_timeline';
-import { useIsExperimentalFeatureEnabled } from '../../common/hooks/use_experimental_features';
 import { useSourcererDataView } from '../../sourcerer/containers';
 import { useDiscoverState } from '../../timelines/components/timeline/tabs/esql/use_discover_state';
 
@@ -63,8 +62,6 @@ export const SendToTimelineButton: FC<PropsWithChildren<SendToTimelineButtonProp
   const { dataViewId: timelineDataViewId } = useSourcererDataView(SourcererScopeName.timeline);
   const { setDiscoverAppState } = useDiscoverState();
 
-  const isEsqlTabInTimelineDisabled = useIsExperimentalFeatureEnabled('timelineEsqlTabDisabled');
-
   const signalIndexName = useSelector(sourcererSelectors.signalIndexName);
   const defaultDataView = useSelector(sourcererSelectors.defaultDataView);
 
@@ -245,10 +242,7 @@ export const SendToTimelineButton: FC<PropsWithChildren<SendToTimelineButtonProp
     : ACTION_CANNOT_INVESTIGATE_IN_TIMELINE;
   const isDisabled = !isTimelineBottomBarVisible;
 
-  if (
-    (dataProviders?.[0]?.queryType === 'esql' || dataProviders?.[0]?.queryType === 'sql') &&
-    isEsqlTabInTimelineDisabled
-  ) {
+  if (dataProviders?.[0]?.queryType === 'esql' || dataProviders?.[0]?.queryType === 'sql') {
     return null;
   }
 

x-pack/solutions/security/plugins/security_solution/public/common/hooks/esql/use_esql_availability.ts

@@ -19,9 +19,6 @@ export const useEsqlAvailability = () => {
   const { uiSettings } = useKibana().services;
   const isEsqlAdvancedSettingEnabled = uiSettings?.get(ENABLE_ESQL);
 
-  const isTimelineEsqlFeatureFlagDisabled =
-    useIsExperimentalFeatureEnabled('timelineEsqlTabDisabled');
-
   const isEsqlRuleTypeEnabled =
     !useIsExperimentalFeatureEnabled('esqlRulesDisabled') && isEsqlAdvancedSettingEnabled;
 
@@ -29,8 +26,7 @@ export const useEsqlAvailability = () => {
     () => ({
       isEsqlAdvancedSettingEnabled,
       isEsqlRuleTypeEnabled,
-      isTimelineEsqlEnabledByFeatureFlag: !isTimelineEsqlFeatureFlagDisabled,
     }),
-    [isEsqlAdvancedSettingEnabled, isTimelineEsqlFeatureFlagDisabled, isEsqlRuleTypeEnabled]
+    [isEsqlAdvancedSettingEnabled, isEsqlRuleTypeEnabled]
   );
 };

x-pack/solutions/security/plugins/security_solution/public/common/hooks/timeline/use_init_timeline_url_param.ts

@@ -10,17 +10,14 @@ import { safeDecode } from '@kbn/rison';
 import { useSelector } from 'react-redux';
 
 import type { State } from '../../store';
-import { TimelineId, TimelineTabs } from '../../../../common/types';
+import { TimelineId } from '../../../../common/types';
 import { useInitializeUrlParam } from '../../utils/global_query_string';
 import { useQueryTimelineById } from '../../../timelines/components/open_timeline/helpers';
 import type { TimelineModel, TimelineUrl } from '../../../timelines/store/model';
 import { selectTimelineById } from '../../../timelines/store/selectors';
 import { URL_PARAM_KEY } from '../use_url_state';
-import { useIsExperimentalFeatureEnabled } from '../use_experimental_features';
 
 export const useInitTimelineFromUrlParam = () => {
-  const isEsqlTabDisabled = useIsExperimentalFeatureEnabled('timelineEsqlTabDisabled');
-
   const queryTimelineById = useQueryTimelineById();
   const activeTimeline = useSelector((state: State) =>
     selectTimelineById(state, TimelineId.active)
@@ -30,10 +27,7 @@ export const useInitTimelineFromUrlParam = () => {
     (initialState: TimelineUrl | null) => {
       if (initialState != null) {
         queryTimelineById({
-          activeTimelineTab:
-            initialState.activeTab === TimelineTabs.esql && isEsqlTabDisabled
-              ? TimelineTabs.query
-              : initialState.activeTab,
+          activeTimelineTab: initialState.activeTab,
           duplicate: false,
           graphEventId: initialState.graphEventId,
           timelineId: initialState.id,
@@ -42,7 +36,7 @@ export const useInitTimelineFromUrlParam = () => {
         });
       }
     },
-    [isEsqlTabDisabled, queryTimelineById]
+    [queryTimelineById]
   );
 
   useEffect(() => {

x-pack/solutions/security/plugins/security_solution/public/timelines/components/timeline/tabs/index.test.tsx

@@ -39,7 +39,6 @@ jest.mock('react-router-dom', () => {
 jest.mock('../../../../common/hooks/esql/use_esql_availability', () => ({
   useEsqlAvailability: jest.fn().mockReturnValue({
     isEsqlAdvancedSettingEnabled: true,
-    isTimelineEsqlEnabledByFeatureFlag: true,
   }),
 }));
 
@@ -73,22 +72,6 @@ describe('Timeline', () => {
       it('should not show the esql tab when the advanced setting is disabled', async () => {
         useEsqlAvailabilityMock.mockReturnValue({
           isEsqlAdvancedSettingEnabled: false,
-          isTimelineEsqlEnabledByFeatureFlag: true,
-        });
-        render(
-          <TestProviders>
-            <TabsContent {...defaultProps} />
-          </TestProviders>
-        );
-
-        await waitFor(() => {
-          expect(screen.queryByTestId(esqlTabSubj)).toBeNull();
-        });
-      });
-      it('should not show the esql tab when the esql is disabled by feature flag', async () => {
-        useEsqlAvailabilityMock.mockReturnValue({
-          isEsqlAdvancedSettingEnabled: false,
-          isTimelineEsqlEnabledByFeatureFlag: false,
         });
         render(
           <TestProviders>
@@ -113,7 +96,6 @@ describe('Timeline', () => {
       it('should show the esql tab when the advanced setting is disabled', async () => {
         useEsqlAvailabilityMock.mockReturnValue({
           isESQLTabInTimelineEnabled: false,
-          isTimelineEsqlEnabledByFeatureFlag: true,
         });
 
         render(
@@ -126,23 +108,6 @@ describe('Timeline', () => {
           expect(screen.queryByTestId(esqlTabSubj)).toBeVisible();
         });
       });
-
-      it('should not show the esql tab when the esql is disabled by the feature flag', async () => {
-        useEsqlAvailabilityMock.mockReturnValue({
-          isESQLTabInTimelineEnabled: true,
-          isTimelineEsqlEnabledByFeatureFlag: false,
-        });
-
-        render(
-          <TestProviders store={mockStore}>
-            <TabsContent {...defaultProps} />
-          </TestProviders>
-        );
-
-        await waitFor(() => {
-          expect(screen.queryByTestId(esqlTabSubj)).toBeNull();
-        });
-      });
     });
   });
 

x-pack/solutions/security/plugins/security_solution/public/timelines/components/timeline/tabs/index.tsx

@@ -107,20 +107,14 @@ const ActiveTimelineTab = memo<ActiveTimelineTabProps>(
     timelineType,
     showTimeline,
   }) => {
-    const { isTimelineEsqlEnabledByFeatureFlag, isEsqlAdvancedSettingEnabled } =
-      useEsqlAvailability();
+    const { isEsqlAdvancedSettingEnabled } = useEsqlAvailability();
     const timelineESQLSavedSearch = useShallowEqualSelector((state) =>
       selectTimelineESQLSavedSearchId(state, timelineId)
     );
-    const shouldShowESQLTab = useMemo(() => {
-      // disabling esql feature from feature flag should unequivocally hide the tab
-      // irrespective of the fact that the advanced setting is enabled or
-      // not or existing esql query is present or not
-      if (!isTimelineEsqlEnabledByFeatureFlag) {
-        return false;
-      }
-      return isEsqlAdvancedSettingEnabled || timelineESQLSavedSearch != null;
-    }, [isEsqlAdvancedSettingEnabled, isTimelineEsqlEnabledByFeatureFlag, timelineESQLSavedSearch]);
+    const shouldShowESQLTab = useMemo(
+      () => isEsqlAdvancedSettingEnabled || timelineESQLSavedSearch != null,
+      [isEsqlAdvancedSettingEnabled, timelineESQLSavedSearch]
+    );
     const getTab = useCallback(
       (tab: TimelineTabs) => {
         switch (tab) {
@@ -246,8 +240,7 @@ const TabsContentComponent: React.FC<BasicTimelineTab> = ({
   const getAppNotes = useMemo(() => getNotesSelector(), []);
   const getTimelineNoteIds = useMemo(() => getNoteIdsSelector(), []);
   const getTimelinePinnedEventNotes = useMemo(() => getEventIdToNoteIdsSelector(), []);
-  const { isEsqlAdvancedSettingEnabled, isTimelineEsqlEnabledByFeatureFlag } =
-    useEsqlAvailability();
+  const { isEsqlAdvancedSettingEnabled } = useEsqlAvailability();
 
   const timelineESQLSavedSearch = useShallowEqualSelector((state) =>
     selectTimelineESQLSavedSearchId(state, timelineId)
@@ -263,15 +256,10 @@ const TabsContentComponent: React.FC<BasicTimelineTab> = ({
 
   const activeTab = useShallowEqualSelector((state) => getActiveTab(state, timelineId));
   const showTimeline = useShallowEqualSelector((state) => getShowTimeline(state, timelineId));
-  const shouldShowESQLTab = useMemo(() => {
-    // disabling esql feature from feature flag should unequivocally hide the tab
-    // irrespective of the fact that the advanced setting is enabled or
-    // not or existing esql query is present or not
-    if (!isTimelineEsqlEnabledByFeatureFlag) {
-      return false;
-    }
-    return isEsqlAdvancedSettingEnabled || timelineESQLSavedSearch != null;
-  }, [isEsqlAdvancedSettingEnabled, isTimelineEsqlEnabledByFeatureFlag, timelineESQLSavedSearch]);
+  const shouldShowESQLTab = useMemo(
+    () => isEsqlAdvancedSettingEnabled || timelineESQLSavedSearch != null,
+    [isEsqlAdvancedSettingEnabled, timelineESQLSavedSearch]
+  );
 
   const numberOfPinnedEvents = useShallowEqualSelector((state) =>
     getNumberOfPinnedEvents(state, timelineId)