Debugger: re-add old qobject children dumper for qtversion < 6

Change-Id: Icbafb7c22d18247f89a8aa6a5029c9914d251c2e
Reviewed-by: Christian Stenger <christian.stenger@qt.io>
Reviewed-by: hjk <hjk@qt.io>

share/qtcreator/debugger/dumper.py

@@ -1897,9 +1897,31 @@ class DumperBase():
             with SubItem(self, '[children]'):
                 if not self.isCli:
                     self.putSortGroup(8)
+
+                if self.qtVersion() >= 0x60000:
                     dvtablePtr, qptr, parentPtr, children \
                         = self.split('ppp{QList<QObject*>}', dd)
                     self.putItem(children)
+                else:
+                    base = self.extractPointer(dd + 3 * ptrSize)  # It's a QList<QObject *>
+                    begin = self.extractInt(base + 8)
+                    end = self.extractInt(base + 12)
+                    array = base + 16
+                    if self.qtVersion() < 0x50000:
+                        array += ptrSize
+                    self.check(begin >= 0 and end >= 0 and end <= 1000 * 1000 * 1000)
+                    size = end - begin
+                    self.check(size >= 0)
+                    self.putItemCount(size)
+                    if size > 0:
+                        self.putExpandable()
+                    if self.isExpanded():
+                        addrBase = array + begin * ptrSize
+                        with Children(self, size):
+                            for i in self.childRange():
+                                with SubItem(self, i):
+                                    childPtr = self.extractPointer(addrBase + i * ptrSize)
+                                    self.putItem(self.createValue(childPtr, qobjectType))
 
         if isQMetaObject:
             with SubItem(self, '[strings]'):