Don't call AcceptCurrentInstantPreview() when the user hits Tab.

chrome/browser/ui/omnibox/omnibox_edit_model.cc

 // Copyright 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/omnibox/omnibox_edit_model.h"
 
 #include <string>
 
 #include "base/auto_reset.h"
 #include "base/format_macros.h"
@@ skipping 249 matching lines @@
 
   // Assume that the gray text we are committing is a search suggestion.
   FinalizeInstantQuery(view_->GetText(),
                        InstantSuggestion(suggestion,
                                          INSTANT_COMPLETE_NOW,
                                          INSTANT_SUGGESTION_SEARCH),
                        skip_inline_autocomplete);
   return true;
 }
 
-bool OmniboxEditModel::AcceptCurrentInstantPreview() {
-  return controller_->GetInstant() &&
-      controller_->GetInstant()->CommitIfPossible(INSTANT_COMMIT_PRESSED_ENTER);
-}
-
 void OmniboxEditModel::OnChanged() {
   // Don't call CurrentMatch() when there's no editing, as in this case we'll
   // never actually use it.  This avoids running the autocomplete providers (and
   // any systems they then spin up) during startup.
   const AutocompleteMatch& current_match = user_input_in_progress_ ?
       CurrentMatch() : AutocompleteMatch();
 
   AutocompleteActionPredictor::Action recommended_action =
       AutocompleteActionPredictor::ACTION_NONE;
   AutocompleteActionPredictor* action_predictor =
@@ skipping 1085 matching lines @@
     instant->OmniboxFocusChanged(state, reason, NULL);
 
   // Update state and notify view if the omnibox has focus and the caret
   // visibility changed.
   const bool was_caret_visible = is_caret_visible();
   focus_state_ = state;
   if (focus_state_ != OMNIBOX_FOCUS_NONE &&
       is_caret_visible() != was_caret_visible)
     view_->ApplyCaretVisibility();
 }