Make it possible to take bindings from properties without private headers

Passing the QExplicitlySharedDataPointer by reference may lead compilers
to wanting to have visibility to the destructor of the contained type
(QPropertyBindingPrivate), which is not public. Fortunately
QExplicitlySharedDataPointer is safe to use with raw pointers and those
can be safely forward declared.

Change-Id: I131ab6363eaee10b6dce196fb2c769e09a5c9557
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

src/corelib/kernel/qproperty.cpp

@@ -102,7 +102,7 @@ QUntypedPropertyBinding QPropertyBase::setBinding(const QUntypedPropertyBinding
 
     if (auto *existingBinding = d.bindingPtr()) {
         if (existingBinding == newBinding.data())
-            return QUntypedPropertyBinding(oldBinding);
+            return QUntypedPropertyBinding(oldBinding.data());
         oldBinding = QPropertyBindingPrivatePtr(existingBinding);
         oldBinding->unlinkAndDeref();
         d_ptr &= FlagMask;
@@ -119,15 +119,15 @@ QUntypedPropertyBinding QPropertyBase::setBinding(const QUntypedPropertyBinding
         d_ptr &= ~BindingBit;
     }
 
-    return QUntypedPropertyBinding(oldBinding);
+    return QUntypedPropertyBinding(oldBinding.data());
 }
 
-QPropertyBindingPrivatePtr QPropertyBase::binding()
+QPropertyBindingPrivate *QPropertyBase::binding()
 {
     QPropertyBasePointer d{this};
     if (auto binding = d.bindingPtr())
-        return QPropertyBindingPrivatePtr(binding);
-    return QPropertyBindingPrivatePtr();
+        return binding;
+    return nullptr;
 }
 
 QPropertyBindingPrivate *QPropertyBasePointer::bindingPtr() const

src/corelib/kernel/qproperty.h

@@ -137,7 +137,7 @@ public:
 
     QMetaType valueMetaType() const;
 
-    explicit QUntypedPropertyBinding(const QPropertyBindingPrivatePtr &priv);
+    explicit QUntypedPropertyBinding(QPropertyBindingPrivate *priv);
 private:
     friend class QtPrivate::QPropertyBase;
     friend class QPropertyBindingPrivate;

src/corelib/kernel/qpropertybinding.cpp

@@ -134,7 +134,7 @@ QUntypedPropertyBinding &QUntypedPropertyBinding::operator=(QUntypedPropertyBind
     return *this;
 }
 
-QUntypedPropertyBinding::QUntypedPropertyBinding(const QPropertyBindingPrivatePtr &priv)
+QUntypedPropertyBinding::QUntypedPropertyBinding(QPropertyBindingPrivate *priv)
     : d(priv)
 {
 }

src/corelib/kernel/qpropertyprivate.h

@@ -83,7 +83,7 @@ public:
     bool hasBinding() const { return d_ptr & BindingBit; }
 
     QUntypedPropertyBinding setBinding(const QUntypedPropertyBinding &newBinding, void *propertyDataPtr);
-    QPropertyBindingPrivatePtr binding();
+    QPropertyBindingPrivate *binding();
 
     void evaluateIfDirty();
     void removeBinding();