Revert of Revert of [AiS] Merge answers into highest-scoring result

components/omnibox/base_search_provider.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/omnibox/base_search_provider.h"
 
 #include "base/i18n/case_conversion.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "components/metrics/proto/omnibox_event.pb.h"
@@ skipping 402 matching lines @@
         // is sufficiently relevant that the user is likely to choose it.
         // Surely setting the prefetch bit on a match of even higher relevance
         // won't violate this assumption.
         should_prefetch |= ShouldPrefetch(i.first->second);
         i.first->second.RecordAdditionalInfo(kShouldPrefetchKey,
                                              should_prefetch ? kTrue : kFalse);
         if (should_prefetch)
           i.first->second.RecordAdditionalInfo(kSuggestMetadataKey, metadata);
       }
     }
+    // Copy over answer data from lower-ranking item, if necessary.
+    // This depends on the lower-ranking item always being added last - see
+    // use of push_back above.
+    AutocompleteMatch& more_relevant_match = i.first->second;
+    const AutocompleteMatch& less_relevant_match =
+        more_relevant_match.duplicate_matches.back();
+    if (!less_relevant_match.answer_type.empty() &&
+        more_relevant_match.answer_type.empty()) {
+      more_relevant_match.answer_type = less_relevant_match.answer_type;
+      more_relevant_match.answer_contents = less_relevant_match.answer_contents;
+    }
   }
 }
 
 bool BaseSearchProvider::ParseSuggestResults(
     const base::Value& root_val,
     int default_result_relevance,
     bool is_keyword_result,
     SearchSuggestionParser::Results* results) {
   if (!SearchSuggestionParser::ParseSuggestResults(
       root_val, GetInput(is_keyword_result),
@@ skipping 27 matching lines @@
 }
 
 void BaseSearchProvider::OnDeletionComplete(
     bool success, SuggestionDeletionHandler* handler) {
   RecordDeletionResult(success);
   SuggestionDeletionHandlers::iterator it = std::find(
       deletion_handlers_.begin(), deletion_handlers_.end(), handler);
   DCHECK(it != deletion_handlers_.end());
   deletion_handlers_.erase(it);
 }