[Security Solution][Investigations] - 8.7 minor fixes (elastic#152284)

## Summary

This PR includes minor fixes for the following items by commit

**[Timeline ui alignment fix]**
elastic#149017 -
elastic@0128149
**[Saving empty eql query]**
elastic#148950 -
elastic@b9715cb
**[Re-add alert count to top n]**
elastic#148631 -
elastic@4c8d1e6

x-pack/plugins/security_solution/cypress/e2e/timelines/creation.cy.ts

@@ -22,6 +22,7 @@ import {
   TIMELINE_TAB_CONTENT_GRAPHS_NOTES,
   EDIT_TIMELINE_BTN,
   EDIT_TIMELINE_TOOLTIP,
+  TIMELINE_CORRELATION_INPUT,
 } from '../../screens/timeline';
 import { createTimelineTemplate } from '../../tasks/api_calls/timelines';
 
@@ -41,9 +42,11 @@ import {
   goToQueryTab,
   pinFirstEvent,
   populateTimeline,
+  waitForTimelineChanges,
 } from '../../tasks/timeline';
 
 import { OVERVIEW_URL, TIMELINE_TEMPLATES_URL } from '../../urls/navigation';
+import { EQL_QUERY_VALIDATION_ERROR } from '../../screens/create_new_rule';
 
 describe('Create a timeline from a template', () => {
   before(() => {
@@ -154,5 +157,67 @@ describe('Timelines', (): void => {
         .then(parseInt)
         .should('be.gt', 0);
     });
+
+    // Skipped in this PR until the underlying re-renders are fixed: https://github.com/elastic/kibana/pull/152284
+    describe.skip('correlation tab', () => {
+      it('should update timeline after adding eql', () => {
+        cy.intercept('PATCH', '/api/timeline').as('updateTimeline');
+        const eql = 'any where process.name == "zsh"';
+        addEqlToTimeline(eql);
+
+        cy.wait('@updateTimeline', { timeout: 10000 }).its('response.statusCode').should('eq', 200);
+
+        cy.get(`${TIMELINE_TAB_CONTENT_EQL} ${SERVER_SIDE_EVENT_COUNT}`)
+          .invoke('text')
+          .then(parseInt)
+          .should('be.gt', 0);
+      });
+
+      describe.skip('updates', () => {
+        const eql = 'any where process.name == "zsh"';
+        beforeEach(() => {
+          cy.intercept('PATCH', '/api/timeline').as('updateTimeline');
+          addEqlToTimeline(eql);
+          // TODO: It may need a further refactor to handle the frequency with which react calls this api
+          // Since it's based on real time text changes...and real time query validation
+          // there's almost no guarantee on the number of calls, so a cypress.wait may actually be more appropriate
+          cy.wait('@updateTimeline');
+          cy.wait('@updateTimeline');
+          cy.reload();
+          cy.get(TIMELINE_CORRELATION_INPUT).should('be.visible');
+          cy.get(TIMELINE_CORRELATION_INPUT).should('have.text', eql);
+        });
+
+        it('should update timeline after removing eql', () => {
+          cy.intercept('PATCH', '/api/timeline').as('updateTimeline');
+          cy.get(TIMELINE_CORRELATION_INPUT).should('be.visible');
+          waitForTimelineChanges();
+          cy.get(TIMELINE_CORRELATION_INPUT).type('{selectAll} {del}').clear();
+          // TODO: It may need a further refactor to handle the frequency with which react calls this api
+          // Since it's based on real time text changes...and real time query validation
+          // there's almost no guarantee on the number of calls, so a cypress.wait may actually be more appropriate
+          cy.wait('@updateTimeline');
+          cy.wait('@updateTimeline');
+          cy.wait('@updateTimeline');
+          cy.wait('@updateTimeline');
+          waitForTimelineChanges();
+          cy.reload();
+          cy.get(TIMELINE_CORRELATION_INPUT).should('be.visible');
+
+          cy.get(TIMELINE_CORRELATION_INPUT).should('have.text', '');
+        });
+
+        it('should NOT update timeline after adding wrong eql', () => {
+          cy.intercept('PATCH', '/api/timeline').as('updateTimeline');
+          const nonFunctionalEql = 'this is not valid eql';
+          addEqlToTimeline(nonFunctionalEql);
+          cy.get(EQL_QUERY_VALIDATION_ERROR).should('be.visible');
+          cy.reload();
+          cy.get(TIMELINE_CORRELATION_INPUT).should('be.visible');
+
+          cy.get(TIMELINE_CORRELATION_INPUT).should('have.text', eql);
+        });
+      });
+    });
   });
 });

x-pack/plugins/security_solution/cypress/screens/create_new_rule.ts

@@ -89,6 +89,8 @@ export const EQL_QUERY_INPUT = '[data-test-subj="eqlQueryBarTextInput"]';
 
 export const EQL_QUERY_VALIDATION_SPINNER = '[data-test-subj="eql-validation-loading"]';
 
+export const EQL_QUERY_VALIDATION_ERROR = '[data-test-subj="eql-validation-errors-popover-button"]';
+
 export const IMPORT_QUERY_FROM_SAVED_TIMELINE_LINK =
   '[data-test-subj="importQueryFromSavedTimeline"]';
 

x-pack/plugins/security_solution/public/detections/components/alerts_kpis/alerts_histogram_panel/index.tsx

@@ -391,15 +391,14 @@ export const AlertsHistogramPanel = memo<AlertsHistogramPanelProps>(
             alignHeader={alignHeader}
             id={uniqueQueryId}
             inspectTitle={inspectTitle}
-            outerDirection="row"
+            outerDirection="column"
             title={titleText}
             titleSize={titleSize}
             toggleStatus={showHistogram}
             toggleQuery={hideQueryToggle ? undefined : toggleQuery}
             showInspectButton={isChartEmbeddablesEnabled ? false : chartOptionsContextMenu == null}
             subtitle={!isInitialLoading && showTotalAlertsCount && totalAlerts}
             isInspectDisabled={isInspectDisabled}
-            hideSubtitle
           >
             <EuiFlexGroup alignItems="flexStart" data-test-subj="panelFlexGroup" gutterSize="none">
               <EuiFlexItem grow={false}>

x-pack/plugins/security_solution/public/timelines/components/timeline/eql_tab_content/index.tsx

@@ -69,11 +69,12 @@ const StyledEuiFlyoutHeader = styled(EuiFlyoutHeader)`
   box-shadow: none;
   display: flex;
   flex-direction: column;
+  margin-top: ${({ theme }) => theme.eui.euiSizeM}
   padding: 0;
 
   &.euiFlyoutHeader {
     ${({ theme }) =>
-      `padding: 0 ${theme.eui.euiSizeS} ${theme.eui.euiSizeS} ${theme.eui.euiSizeS};`}
+      `padding: 0 ${theme.eui.euiSizeM} ${theme.eui.euiSizeS} ${theme.eui.euiSizeS};`}
   }
 `;
 

x-pack/plugins/security_solution/public/timelines/components/timeline/query_bar/eql/index.tsx

@@ -107,6 +107,8 @@ export const EqlQueryBarTimeline = memo(({ timelineId }: { timelineId: string })
     watch: ['eqlQueryBar'],
   });
 
+  const prevEqlQuery = useRef<TimelineEqlQueryBar['eqlQueryBar']['query']['query']>('');
+
   const optionsData = useMemo(
     () =>
       isEmpty(indexPattern.fields)
@@ -156,10 +158,11 @@ export const EqlQueryBarTimeline = memo(({ timelineId }: { timelineId: string })
   useEffect(() => {
     if (
       formEqlQueryBar != null &&
-      !isEmpty(formEqlQueryBar.query.query) &&
+      prevEqlQuery.current !== formEqlQueryBar.query.query &&
       isQueryBarValid &&
       !isQueryBarValidating
     ) {
+      prevEqlQuery.current = formEqlQueryBar.query.query;
       dispatch(
         timelineActions.updateEqlOptions({
           id: timelineId,