A simple version of search term replacement for testing .

chrome/browser/ui/cocoa/omnibox/omnibox_view_mac.mm

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/cocoa/omnibox/omnibox_view_mac.h"
 
 #include <Carbon/Carbon.h>  // kVK_Return
 
 #include "base/property_bag.h"
 #include "base/string_util.h"
@@ skipping 179 matching lines @@
   OmniboxViewMacState state(model()->GetStateForTabSwitch(), hasFocus, range);
   StoreStateToTab(tab, state);
 }
 
 void OmniboxViewMac::Update(const WebContents* tab_for_state_restoring) {
   // TODO(shess): It seems like if the tab is non-NULL, then this code
   // shouldn't need to be called at all.  When coded that way, I find
   // that the field isn't always updated correctly.  Figure out why
   // this is.  Maybe this method should be refactored into more
   // specific cases.
-  bool user_visible = model()->UpdatePermanentText(toolbar_model()->GetText());
+  bool user_visible =
+      model()->UpdatePermanentText(toolbar_model()->GetText(true));
 
   if (tab_for_state_restoring) {
     RevertAll();
 
     const OmniboxViewMacState* state = GetStateFromTab(tab_for_state_restoring);
     if (state) {
       // Should restore the user's text via SetUserText().
       model()->RestoreState(state->model_state);
 
       // Restore focus and selection if they were present when the tab
@@ skipping 773 matching lines @@
 NSUInteger OmniboxViewMac::GetTextLength() const {
   return ([field_ currentEditor] ?
           [[[field_ currentEditor] string] length] :
           [[field_ stringValue] length]) - suggest_text_length_;
 }
 
 bool OmniboxViewMac::IsCaretAtEnd() const {
   const NSRange selection = GetSelectedRange();
   return selection.length == 0 && selection.location == GetTextLength();
 }