Eliminate the "clock" icon in the omnibox dropdown. The distinction between this and the globe was…

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 127 matching lines @@
     // From the autocomplete popup, or the star icon at the RHS of the
     // text field.
     case IDR_STAR: image_name = @"star.pdf"; break;
     case IDR_STAR_LIT: image_name = @"star_lit.pdf"; break;
 
     // Values from |AutocompleteMatch::TypeToIcon()|.
     case IDR_OMNIBOX_SEARCH:
       image_name = @"omnibox_search.pdf"; break;
     case IDR_OMNIBOX_HTTP:
       image_name = @"omnibox_http.pdf"; break;
-    case IDR_OMNIBOX_HISTORY:
-      image_name = @"omnibox_history.pdf"; break;
     case IDR_OMNIBOX_EXTENSION_APP:
       image_name = @"omnibox_extension_app.pdf"; break;
 
     // Values from |ToolbarModel::GetIcon()|.
     case IDR_OMNIBOX_HTTPS_VALID:
       image_name = @"omnibox_https_valid.pdf"; break;
     case IDR_OMNIBOX_HTTPS_WARNING:
       image_name = @"omnibox_https_warning.pdf"; break;
     case IDR_OMNIBOX_HTTPS_INVALID:
       image_name = @"omnibox_https_invalid.pdf"; break;
@@ skipping 963 matching lines @@
 
 void OmniboxViewMac::PlaceCaretAt(NSUInteger pos) {
   DCHECK(pos <= GetTextLength());
   SetSelectedRange(NSMakeRange(pos, pos));
 }
 
 bool OmniboxViewMac::IsCaretAtEnd() const {
   const NSRange selection = GetSelectedRange();
   return selection.length == 0 && selection.location == GetTextLength();
 }