[omnibox] Set is_answer correctly.

This CL fixes a bug where results are never set to be answers due to
circular logic.

Bug: 1130372
Change-Id: I177dcaaa7a67e23cc31e49ea2f17f1a3ca249fb3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2437317Reviewed-by: Thanh Nguyen <thanhdng@chromium.org>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Rachel Wong <wrong@chromium.org>
Cr-Commit-Position: refs/heads/master@{#812468}

chrome/browser/ui/app_list/search/omnibox_result.cc

@@ -160,10 +160,12 @@ OmniboxResult::OmniboxResult(Profile* profile,
   set_result_subtype(static_cast<int>(match_.type));
   SetMetricsType(GetSearchResultType());
 
-  if (ShouldDisplayAsAnswer()) {
+  if (app_list_features::IsOmniboxRichEntitiesEnabled()) {
     SetIsAnswer(match_.answer.has_value());
-    // The answer subtype overrides the match subtype.
-    set_result_subtype(static_cast<int>(match_.answer->type()));
+    if (is_answer()) {
+      // The answer subtype overrides the match subtype.
+      set_result_subtype(static_cast<int>(match_.answer->type()));
+    }
   }
 
   // Derive relevance from omnibox relevance and normalize it to [0, 1].