[Android] Allow setting recently visited search engines as default search engine

components/search_engines/template_url_service.cc

Index: components/search_engines/template_url_service.cc
diff --git a/components/search_engines/template_url_service.cc b/components/search_engines/template_url_service.cc
index 664fa3390a3a2ec1775d070a925493347201018e..ea1c93f73dcd2d7128db759e5d34686170042bcb 100644
--- a/components/search_engines/template_url_service.cc
+++ b/components/search_engines/template_url_service.cc
@@ -395,10 +395,15 @@ bool TemplateURLService::CanAddAutogeneratedKeyword(
       CanAddAutogeneratedKeywordForHost(url.host());
 }
 
+bool TemplateURLService::ShowInPrepopulatedList(const TemplateURL* t_url) {
+  return (t_url->prepopulate_id() > 0 || t_url->created_by_policy()) &&
+      t_url->SupportsReplacement(search_terms_data());
+}
+
 bool TemplateURLService::ShowInDefaultList(const TemplateURL* t_url) {
-  return (t_url == default_search_provider_ || t_url->prepopulate_id() > 0 ||
-          t_url->created_by_policy()) &&
-         t_url->SupportsReplacement(search_terms_data());
+  return (t_url == default_search_provider_  &&
+      t_url->SupportsReplacement(search_terms_data())) ||

[Peter Kasting, 2016/11/23 21:30:27]

I don't think we should explicitly check SupportsReplacement() here, since if
something is already the default search provider, it presumably supports
replacement, but even if somehow it doesn't, it surely should be shown in the
default list.

[ltian, 2016/11/29 02:44:03]

Done.

+      ShowInPrepopulatedList(t_url);
 }
 
 void TemplateURLService::AddMatchingKeywords(