Don't demote top match for certain match types.

chrome/browser/autocomplete/autocomplete_match.cc

Index: chrome/browser/autocomplete/autocomplete_match.cc
diff --git a/chrome/browser/autocomplete/autocomplete_match.cc b/chrome/browser/autocomplete/autocomplete_match.cc
index 3346d35699647ba67c61b6af42393c1ab50f5d70..e9e649163f626a61c6bbc4d704b1649c37e4e942 100644
--- a/chrome/browser/autocomplete/autocomplete_match.cc
+++ b/chrome/browser/autocomplete/autocomplete_match.cc
@@ -44,6 +44,7 @@ AutocompleteMatch::AutocompleteMatch()
       typed_count(-1),
       deletable(false),
       allowed_to_be_default_match(false),
+      demoteable(true),
       transition(content::PAGE_TRANSITION_GENERATED),
       is_history_what_you_typed_match(false),
       type(AutocompleteMatchType::SEARCH_WHAT_YOU_TYPED),
@@ -60,6 +61,7 @@ AutocompleteMatch::AutocompleteMatch(AutocompleteProvider* provider,
       typed_count(-1),
       deletable(deletable),
       allowed_to_be_default_match(false),
+      demoteable(true),
       transition(content::PAGE_TRANSITION_TYPED),
       is_history_what_you_typed_match(false),
       type(type),
@@ -75,6 +77,7 @@ AutocompleteMatch::AutocompleteMatch(const AutocompleteMatch& match)
       fill_into_edit(match.fill_into_edit),
       inline_autocompletion(match.inline_autocompletion),
       allowed_to_be_default_match(match.allowed_to_be_default_match),
+      demoteable(match.demoteable),
       destination_url(match.destination_url),
       stripped_destination_url(match.stripped_destination_url),
       contents(match.contents),
@@ -110,6 +113,7 @@ AutocompleteMatch& AutocompleteMatch::operator=(
   fill_into_edit = match.fill_into_edit;
   inline_autocompletion = match.inline_autocompletion;
   allowed_to_be_default_match = match.allowed_to_be_default_match;
+  demoteable = match.demoteable;
   destination_url = match.destination_url;
   stripped_destination_url = match.stripped_destination_url;
   contents = match.contents;