chrome: Add out-of-line copy ctors for complex classes.

chrome/browser/predictors/autocomplete_action_predictor.cc

 // 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/predictors/autocomplete_action_predictor.h"
 
 #include <math.h>
 #include <stddef.h>
 
 #include <vector>
@@ skipping 574 matching lines @@
 
 void AutocompleteActionPredictor::OnHistoryServiceLoaded(
     history::HistoryService* history_service) {
   TryDeleteOldEntries(history_service);
   history_service_observer_.Remove(history_service);
 }
 
 AutocompleteActionPredictor::TransitionalMatch::TransitionalMatch() {
 }
 
+AutocompleteActionPredictor::TransitionalMatch::TransitionalMatch(
+    const TransitionalMatch& other) = default;
+
 AutocompleteActionPredictor::TransitionalMatch::~TransitionalMatch() {
 }
 
 }  // namespace predictors