Added move constructor to PassRefPtr.

third_party/WebKit/Source/wtf/PassRefPtr.h

 /*
  *  Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  *
  *  This library is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU Library General Public
  *  License as published by the Free Software Foundation; either
  *  version 2 of the License, or (at your option) any later version.
  *
  *  This library is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 52 matching lines @@
 public:
     PassRefPtr() : m_ptr(nullptr) {}
     PassRefPtr(std::nullptr_t) : m_ptr(nullptr) {}
     PassRefPtr(T* ptr) : m_ptr(ptr) { refIfNotNull(ptr); }
     explicit PassRefPtr(T& ptr) : m_ptr(&ptr) { m_ptr->ref(); }
     // It somewhat breaks the type system to allow transfer of ownership out of
     // a const PassRefPtr. However, it makes it much easier to work with
     // PassRefPtr temporaries, and we don't have a need to use real const
     // PassRefPtrs anyway.
     PassRefPtr(const PassRefPtr& o) : m_ptr(o.leakRef()) {}
+    PassRefPtr(const PassRefPtr&& o) : m_ptr(o.leakRef()) {}

[Yuta Kitamura, 2016/08/24 08:26:22]

Remove "const" here. It's confusing to have "const T&&" for any type T, because
an rvalue reference represents a temporary value that is not stored anywhere,
and it's almost always non-const.

In the first place, leakRef() really shouldn't be marked const, as it modifies
m_ptr. But I don't feel it worth fixing because we are trying to kill
PassRefPtr.

[Bugs Nash, 2016/08/29 01:50:24]

Done.

     template <typename U> PassRefPtr(const PassRefPtr<U>& o, EnsurePtrConvertibleArgDecl(U, T)) : m_ptr(o.leakRef()) {}
 
     ALWAYS_INLINE ~PassRefPtr() { derefIfNotNull(m_ptr); }
 
     template <typename U> PassRefPtr(const RefPtr<U>&, EnsurePtrConvertibleArgDecl(U, T));
     template <typename U> PassRefPtr(RefPtr<U>&&, EnsurePtrConvertibleArgDecl(U, T));
 
     T* get() const { return m_ptr; }
 
     T* leakRef() const WARN_UNUSED_RETURN;
@@ skipping 126 matching lines @@
 {
     return p.get();
 }
 
 } // namespace WTF
 
 using WTF::PassRefPtr;
 using WTF::adoptRef;
 
 #endif // WTF_PassRefPtr_h