QSet/QQueue/QStack: use compiler-generated special member functions

They do the right thing (except move special member functions
on MSVC, but that's MSVC's problem).

Change-Id: I699e1be83c0568821f8c6b84394a2713bb22e8e7
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/tools/qhash.h

@@ -916,6 +916,9 @@ public:
             insert(it->first, it->second);
     }
 #endif
+    // compiler-generated copy/move ctors/assignment operators are fine!
+    // compiler-generated destructor is fine!
+
     QMultiHash(const QHash<Key, T> &other) : QHash<Key, T>(other) {}
     void swap(QMultiHash &other) { QHash<Key, T>::swap(other); } // prevent QMultiHash<->QHash swaps
 

src/corelib/tools/qqueue.h

@@ -43,8 +43,7 @@ template <class T>
 class QQueue : public QList<T>
 {
 public:
-    inline QQueue() {}
-    inline ~QQueue() {}
+    // compiler-generated special member functions are fine!
     inline void swap(QQueue<T> &other) { QList<T>::swap(other); } // prevent QList<->QQueue swaps
 #ifndef Q_QDOC
     // bring in QList::swap(int, int). We cannot say using QList<T>::swap,

src/corelib/tools/qset.h

@@ -57,15 +57,9 @@ public:
             insert(*it);
     }
 #endif
-    inline QSet(const QSet<T> &other) : q_hash(other.q_hash) {}
+    // compiler-generated copy/move ctor/assignment operators are fine!
+    // compiler-generated destructor is fine!
 
-    inline QSet<T> &operator=(const QSet<T> &other)
-        { q_hash = other.q_hash; return *this; }
-#ifdef Q_COMPILER_RVALUE_REFS
-    inline QSet(QSet &&other) : q_hash(qMove(other.q_hash)) {}
-    inline QSet<T> &operator=(QSet<T> &&other)
-        { qSwap(q_hash, other.q_hash); return *this; }
-#endif
     inline void swap(QSet<T> &other) { q_hash.swap(other.q_hash); }
 
     inline bool operator==(const QSet<T> &other) const

src/corelib/tools/qstack.h

@@ -43,8 +43,7 @@ template<class T>
 class QStack : public QVector<T>
 {
 public:
-    inline QStack() {}
-    inline ~QStack() {}
+    // compiler-generated special member functions are fine!
     inline void swap(QStack<T> &other) { QVector<T>::swap(other); } // prevent QVector<->QStack swaps
     inline void push(const T &t) { QVector<T>::append(t); }
     T pop();