Cleanup: Remove for_search param from search::InstantExtendedEnabledParam()

ios/chrome/browser/search_engines/ui_thread_search_terms_data.cc

Index: ios/chrome/browser/search_engines/ui_thread_search_terms_data.cc
diff --git a/ios/chrome/browser/search_engines/ui_thread_search_terms_data.cc b/ios/chrome/browser/search_engines/ui_thread_search_terms_data.cc
index d53f00baddb10042e374ec7909e3ddee80fdb931..44669b1e78844bdb770074d1da391dc2ab5febf9 100644
--- a/ios/chrome/browser/search_engines/ui_thread_search_terms_data.cc
+++ b/ios/chrome/browser/search_engines/ui_thread_search_terms_data.cc
@@ -91,10 +91,9 @@ std::string UIThreadSearchTermsData::GetSuggestRequestIdentifier() const {
   return "chrome-ext-ansg";
 }
 
-std::string UIThreadSearchTermsData::InstantExtendedEnabledParam(
-    bool for_search) const {
+std::string UIThreadSearchTermsData::InstantExtendedEnabledParam() const {
   DCHECK(thread_checker_.CalledOnValidThread());
-  return search::InstantExtendedEnabledParam(for_search);
+  return search::InstantExtendedEnabledParam();
 }
 
 std::string UIThreadSearchTermsData::ForceInstantResultsParam(