Add components/search_engines to the omnibox review watchlist.

Change-Id: Ib8c3ca64d59175dd85f393acfe35c7806783da95
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2555472Reviewed-by: manuk hovanesian <manukh@chromium.org>
Commit-Queue: Justin Donnelly <jdonnelly@chromium.org>
Cr-Commit-Position: refs/heads/master@{#830582}

WATCHLISTS

@@ -1472,7 +1472,8 @@
                   '^chrome/browser/ui/omnibox/|'\
                   '^chrome/browser/ui/.*/location_bar/|'\
                   '^chrome/browser/ui/.*/omnibox/|'\
-                  '^components/omnibox/'
+                  '^components/omnibox/|'\
+                  '^components/search_engines/'
     },
     'optimization_guide': {
       'filepath': 'optimization_guide|'\