OwnPtr, OwnArrayPtr: Use copy/move-and-swap for assignment operators

Source/wtf/OwnPtr.h

Index: Source/wtf/OwnPtr.h
diff --git a/Source/wtf/OwnPtr.h b/Source/wtf/OwnPtr.h
index e5baf9341e8ae4ff56e68536d470c6dedbfb087b..023311c03c9489613f81852a9e7aef8b2e7a17b8 100644
--- a/Source/wtf/OwnPtr.h
+++ b/Source/wtf/OwnPtr.h
@@ -137,19 +137,17 @@ namespace WTF {
 
     template<typename T> inline OwnPtr<T>& OwnPtr<T>::operator=(const PassOwnPtr<T>& o)
     {
-        PtrType ptr = m_ptr;
-        m_ptr = o.leakPtr();
-        ASSERT(!ptr || m_ptr != ptr);
-        deleteOwnedPtr(ptr);
+        ASSERT(!o || o != m_ptr);
+        OwnPtr ptr = o;
+        swap(ptr);
         return *this;
     }
 
     template<typename T> template<typename U> inline OwnPtr<T>& OwnPtr<T>::operator=(const PassOwnPtr<U>& o)
     {
-        PtrType ptr = m_ptr;
-        m_ptr = o.leakPtr();
-        ASSERT(!ptr || m_ptr != ptr);
-        deleteOwnedPtr(ptr);
+        ASSERT(!o || o != m_ptr);
+        OwnPtr ptr = o;
+        swap(ptr);
         return *this;
     }
 
@@ -166,21 +164,17 @@ namespace WTF {
 
     template<typename T> inline OwnPtr<T>& OwnPtr<T>::operator=(OwnPtr<T>&& o)
     {
-        PtrType ptr = m_ptr;
-        m_ptr = o.leakPtr();
-        ASSERT(!ptr || m_ptr != ptr);
-        deleteOwnedPtr(ptr);
-
+        ASSERT(!o || o != m_ptr);
+        OwnPtr ptr = std::move(o);

[Nico, 2013/09/11 18:00:36]

As mentioned several times, we can't use C++11 library features.

This doesn't build on Mac which doesn't have a C++11 standard library:

../../third_party/WebKit/Source/wtf/OwnPtr.h:168:27: error: no member named
'move' in namespace 'std'
        OwnPtr ptr = std::move(o);
                     ~~~~~^

+        swap(ptr);
         return *this;
     }
 
     template<typename T> template<typename U> inline OwnPtr<T>& OwnPtr<T>::operator=(OwnPtr<U>&& o)
     {
-        PtrType ptr = m_ptr;
-        m_ptr = o.leakPtr();
-        ASSERT(!ptr || m_ptr != ptr);
-        deleteOwnedPtr(ptr);
-
+        ASSERT(!o || o != m_ptr);
+        OwnPtr ptr = std::move(o);
+        swap(ptr);
         return *this;
     }
 #endif