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

base/task_scheduler/priority_queue.h

 // 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.
 
 #ifndef BASE_TASK_SCHEDULER_PRIORITY_QUEUE_H_
 #define BASE_TASK_SCHEDULER_PRIORITY_QUEUE_H_
 
 #include <memory>
 #include <queue>
 #include <vector>
@@ skipping 15 matching lines @@
   // An immutable struct combining a Sequence and the sort key that determines
   // its position in a PriorityQueue.
   struct BASE_EXPORT SequenceAndSortKey {
     // Constructs a null SequenceAndSortKey.
     SequenceAndSortKey();
 
     // Constructs a SequenceAndSortKey with the given |sequence| and |sort_key|.
     SequenceAndSortKey(scoped_refptr<Sequence> sequence,
                        const SequenceSortKey& sort_key);
 
+    SequenceAndSortKey(const SequenceAndSortKey& other);
+
     ~SequenceAndSortKey();
 
     // Returns true if this is a null SequenceAndSortKey.
     bool is_null() const { return !sequence; }
 
     const scoped_refptr<Sequence> sequence;
     const SequenceSortKey sort_key;
   };
 
   // A Transaction can perform multiple operations atomically on a
@@ skipping 72 matching lines @@
   // empty.
   const SequenceAndSortKey empty_sequence_and_sort_key_;
 
   DISALLOW_COPY_AND_ASSIGN(PriorityQueue);
 };
 
 }  // namespace internal
 }  // namespace base
 
 #endif  // BASE_TASK_SCHEDULER_PRIORITY_QUEUE_H_