Delete from Sync the artificial search engines created by the omnibox extensions.

chrome/browser/search_engines/chrome_template_url_service_client.cc

Index: chrome/browser/search_engines/chrome_template_url_service_client.cc
diff --git a/chrome/browser/search_engines/chrome_template_url_service_client.cc b/chrome/browser/search_engines/chrome_template_url_service_client.cc
index ba7ec07c52a937afd27f3c76273b8008b429378f..6653ee6c70a236ce8a5e0598ea359bea5e467670 100644
--- a/chrome/browser/search_engines/chrome_template_url_service_client.cc
+++ b/chrome/browser/search_engines/chrome_template_url_service_client.cc
@@ -63,16 +63,9 @@ void ChromeTemplateURLServiceClient::AddKeywordGeneratedVisit(const GURL& url) {
                               history::SOURCE_BROWSED, false);
 }
 
-void ChromeTemplateURLServiceClient::RestoreExtensionInfoIfNecessary(
-    TemplateURL* template_url) {
-  const TemplateURLData& data = template_url->data();
-  GURL url(data.url());
-  if (url.SchemeIs(extensions::kExtensionScheme)) {
-    const std::string& extension_id = url.host();
-    template_url->set_extension_info(
-        base::MakeUnique<TemplateURL::AssociatedExtensionInfo>(extension_id));
-    template_url->set_type(TemplateURL::OMNIBOX_API_EXTENSION);
-  }
+bool ChromeTemplateURLServiceClient::IsOmniboxExtensionURL(
+    const std::string& url) {
+  return GURL(url).SchemeIs(extensions::kExtensionScheme);
 }
 
 void ChromeTemplateURLServiceClient::OnURLVisited(