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

chrome/browser/media/router/issue.cc

 // Copyright 2015 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 "base/guid.h"
 #include "chrome/browser/media/router/issue.h"
 
 namespace media_router {
 
 IssueAction::IssueAction(const IssueAction::Type type) : type_(type) {
@@ skipping 20 matching lines @@
       is_blocking_(is_blocking),
       help_url_(GURL(help_url)) {
   DCHECK(!title_.empty());
   DCHECK(severity_ != FATAL || is_blocking_) << "Severity is " << severity_;
 
   // Check that the default and secondary actions are not of the same type.
   if (!secondary_actions_.empty())
     DCHECK_NE(default_action_.type(), secondary_actions_[0].type());
 }
 
+Issue::Issue(const Issue& other) = default;
+
 Issue::~Issue() {
 }
 
 bool Issue::Equals(const Issue& other) const {
   return id_ == other.id_;
 }
 
 }  // namespace media_router