Make the parent in Partition a QPointer.

This also reverts commit dc9e9651ac.

src/core/partition.cpp

@@ -79,7 +79,8 @@ Partition::~Partition()
     // list of children). As a workaround, always remove a partition from its parent here in the dtor.
     // This presumably fixes 232092, but backporting is too risky until we're sure this doesn't cause
     // side-effects.
-    parent()->remove(this);
+    if (m_Parent)
+        parent()->remove(this);
     clearChildren();
     deleteFileSystem();
 }

src/core/partition.h

@@ -27,6 +27,7 @@
 
 #include <QStringList>
 #include <QtGlobal>
+#include <QPointer>
 
 class Device;
 class OperationStack;
@@ -270,7 +271,7 @@ private:
 
     qint32 m_Number;
     Partitions m_Children;
-    PartitionNode* m_Parent;
+    QPointer< PartitionNode > m_Parent;
     FileSystem* m_FileSystem;
     PartitionRole m_Roles;
     qint64 m_FirstSector;

src/ops/deleteoperation.h

@@ -24,7 +24,6 @@
 
 #include "../ops/operation.h"
 
-#include <QPointer>
 #include <QString>
 
 class Device;
@@ -102,7 +101,7 @@ protected:
 
 private:
     Device& m_TargetDevice;
-    QPointer< Partition > m_DeletedPartition;
+    Partition* m_DeletedPartition;
     ShredAction m_ShredAction;
     Job* m_DeleteFileSystemJob;
     DeletePartitionJob* m_DeletePartitionJob;