Add a URL param to indicate group selection in Instant field trial.

chrome/browser/ui/search_engines/edit_search_engine_controller.cc

Index: chrome/browser/ui/search_engines/edit_search_engine_controller.cc
diff --git a/chrome/browser/ui/search_engines/edit_search_engine_controller.cc b/chrome/browser/ui/search_engines/edit_search_engine_controller.cc
index a0c9b52bf07fb1de02009b939c8413dc0215ac51..93c1ee14d54fa3343457aec05c327390d6dddc8e 100644
--- a/chrome/browser/ui/search_engines/edit_search_engine_controller.cc
+++ b/chrome/browser/ui/search_engines/edit_search_engine_controller.cc
@@ -53,8 +53,9 @@ bool EditSearchEngineController::IsURLValid(
   // If the url has a search term, replace it with a random string and make
   // sure the resulting URL is valid. We don't check the validity of the url
   // with the search term as that is not necessarily valid.
-  return GURL(template_ref.ReplaceSearchTerms(TemplateURL(), ASCIIToUTF16("a"),
-      TemplateURLRef::NO_SUGGESTIONS_AVAILABLE, string16())).is_valid();
+  return GURL(template_ref.ReplaceSearchTerms(NULL, TemplateURL(),
+      ASCIIToUTF16("a"), TemplateURLRef::NO_SUGGESTIONS_AVAILABLE, string16()))
+      .is_valid();
 }
 
 bool EditSearchEngineController::IsKeywordValid(
@@ -136,8 +137,8 @@ std::string EditSearchEngineController::GetFixedUpURL(
   // we need to replace the search terms before testing for the scheme.
   TemplateURL t_url;
   t_url.SetURL(url, 0, 0);
-  std::string expanded_url =
-      t_url.url()->ReplaceSearchTerms(t_url, ASCIIToUTF16("x"), 0, string16());
+  std::string expanded_url = t_url.url()->ReplaceSearchTerms(NULL, t_url,
+      ASCIIToUTF16("x"), 0, string16());
   url_parse::Parsed parts;
   std::string scheme(
       URLFixerUpper::SegmentURL(expanded_url, &parts));
@@ -148,4 +149,3 @@ std::string EditSearchEngineController::GetFixedUpURL(
 
   return url;
 }
-