Fix expected PlacementList sort order.

ui/display/manager/display_manager_utilities.cc

 // Copyright 2016 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 "ui/display/manager/display_manager_utilities.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "base/sys_info.h"
@@ skipping 269 matching lines @@
 std::string DisplayIdListToString(const DisplayIdList& list) {
   std::stringstream s;
   const char* sep = "";
   for (int64_t id : list) {
     s << sep << id;
     sep = ",";
   }
   return s.str();
 }
 
-bool CompareDisplayIds(int64_t id1, int64_t id2) {
-  DCHECK_NE(id1, id2);
-  // Output index is stored in the first 8 bits. See GetDisplayIdFromEDID
-  // in edid_parser.cc.
-  int index_1 = id1 & 0xFF;
-  int index_2 = id2 & 0xFF;
-  DCHECK_NE(index_1, index_2) << id1 << " and " << id2;
-  return Display::IsInternalDisplayId(id1) ||
-         (index_1 < index_2 && !Display::IsInternalDisplayId(id2));
-}
-
 }  // namespace display