An edit for SetText needs to be merged with previous edit for omnibox.

chrome/browser/ui/views/omnibox/omnibox_view_views.cc

 // Copyright (c) 2011 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/views/omnibox/omnibox_view_views.h"
 
 #include "base/logging.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/app/chrome_command_ids.h"
@@ skipping 285 matching lines @@
   textfield_->GetSelectedRange(&selection);
   GetStateAccessor()->SetProperty(
       tab->property_bag(),
       AutocompleteEditState(model_state, ViewState(selection)));
 }
 
 void OmniboxViewViews::Update(const TabContents* contents) {
   // NOTE: We're getting the URL text here from the ToolbarModel.
   bool visibly_changed_permanent_text =
       model_->UpdatePermanentText(WideToUTF16Hack(toolbar_model_->GetText()));
-
   ToolbarModel::SecurityLevel security_level =
         toolbar_model_->GetSecurityLevel();
   bool changed_security_level = (security_level != security_level_);
   security_level_ = security_level;
 
   // TODO(oshima): Copied from gtk implementation which is
   // slightly different from WIN impl. Find out the correct implementation
   // for views-implementation.
   if (contents) {
     RevertAll();
     const AutocompleteEditState* state =
         GetStateAccessor()->GetProperty(contents->property_bag());
     if (state) {
       model_->RestoreState(state->model_state);
 
       // Move the marks for the cursor and the other end of the selection to
       // the previously-saved offsets (but preserve PRIMARY).
       textfield_->SelectRange(state->view_state.selection_range);
+      // We do not carry over the current edit history to another tab.
+      // TODO(oshima): consider saving/restoring edit history.
+      textfield_->ClearEditHistory();
     }
   } else if (visibly_changed_permanent_text) {
     RevertAll();
   } else if (changed_security_level) {
     EmphasizeURLComponents();
   }
 }
 
 void OmniboxViewViews::OpenMatch(const AutocompleteMatch& match,
                                  WindowOpenDisposition disposition,
@@ skipping 360 matching lines @@
   normal_text_style_ = textfield_->CreateTextStyle();
   security_error_scheme_style_ = textfield_->CreateTextStyle();
   secure_scheme_style_ = textfield_->CreateTextStyle();
 
   faded_text_style_->set_foreground(kFadedTextColor);
   normal_text_style_->set_foreground(kNormalTextColor);
   secure_scheme_style_->set_foreground(kSecureSchemeColor);
   security_error_scheme_style_->set_foreground(kSecurityErrorSchemeColor);
   security_error_scheme_style_->set_strike(true);
 }