Transmit a X-Chrome-UMA-Enabled bit to Google domains from clients that have UMA enabled.

chrome/browser/search_engines/template_url_prepopulate_data.cc

Index: chrome/browser/search_engines/template_url_prepopulate_data.cc
diff --git a/chrome/browser/search_engines/template_url_prepopulate_data.cc b/chrome/browser/search_engines/template_url_prepopulate_data.cc
index 5f785ce9b5fb181bfeb017a80956d228a5633145..c8cdcc9a24c2015912a29c880119a3870eb7a384 100644
--- a/chrome/browser/search_engines/template_url_prepopulate_data.cc
+++ b/chrome/browser/search_engines/template_url_prepopulate_data.cc
@@ -3281,8 +3281,10 @@ static const PrepopulatedEngine* GetEngineForURL(const std::string& url) {
   // First special-case Google, because the prepopulate URL for it will not
   // convert to a GURL and thus won't have an origin.  Instead see if the
   // incoming URL's host is "[*.]google.<TLD>".
-  if (google_util::IsGoogleHostname(as_gurl.host()))
+  if (google_util::IsGoogleHostname(as_gurl.host(),
+                                    google_util::DISALLOW_SUBDOMAIN)) {
     return &google;
+  }
 
   // Now check the rest of the prepopulate data.
   GURL origin(as_gurl.GetOrigin());