Safety check: include "Check now" button in Settings search

* Include the previously excluded "Check now" button in the Settings
  search. This lists safety check as a result when searching for "Check
  now" if the button is visible at the moment the search is done.

Bug: 1015841,1114020
Change-Id: I09ba5e15b27371cf6a4aff2105a7bc8f4a33d706
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2339996Reviewed-by: dpapad <dpapad@chromium.org>
Commit-Queue: Rainhard Findling <rainhard@chromium.org>
Cr-Commit-Position: refs/heads/master@{#795996}

chrome/browser/resources/settings/safety_check_page/safety_check_page.html

@@ -20,7 +20,7 @@
           restamp>
         <div class="separator"></div>
         <cr-button id="safetyCheckParentButton" class="action-button"
-            on-click="onRunSafetyCheckClick_" no-search
+            on-click="onRunSafetyCheckClick_"
             aria-label="$i18n{safetyCheckParentButtonAriaLabel}">
           $i18n{safetyCheckParentButton}
         </cr-button>