QCborArray: add const_iterator overloads for insert/erase/extract

They return regular iterators, since the container has been modified.

Change-Id: Id59bdd8f1a804b809e22fffd153f92d4460f9b76
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/serialization/qcborarray.cpp

@@ -327,6 +327,9 @@ void QCborArray::insert(qsizetype i, QCborValue &&value)
 }
 
 /*!
+    \fn QCborValue QCborArray::extract(iterator it)
+    \fn QCborValue QCborArray::extract(const_iterator it)
+
     Extracts a value from the array at the position indicated by iterator \a it
     and returns the value so extracted.
 
@@ -576,6 +579,7 @@ bool QCborArray::contains(const QCborValue &value) const
 
 /*!
     \fn QCborArray::iterator QCborArray::insert(iterator before, const QCborValue &value)
+    \fn QCborArray::iterator QCborArray::insert(const_iterator before, const QCborValue &value)
     \overload
 
     Inserts \a value into this array before element \a before and returns an
@@ -586,6 +590,7 @@ bool QCborArray::contains(const QCborValue &value) const
 
 /*!
     \fn QCborArray::iterator QCborArray::erase(iterator it)
+    \fn QCborArray::iterator QCborArray::erase(const_iterator it)
 
     Removes the element pointed to by the array iterator \a it from this array,
     then returns an iterator to the next element (the one that took the same

src/corelib/serialization/qcborarray.h

@@ -195,6 +195,7 @@ public:
     void prepend(QCborValue &&value) { insert(0, std::move(value)); }
     void append(const QCborValue &value) { insert(-1, value); }
     void append(QCborValue &&value) { insert(-1, std::move(value)); }
+    QCborValue extract(ConstIterator it) { return extract(Iterator{ it.item.d, it.item.i }); }
     QCborValue extract(Iterator it);
     void removeAt(qsizetype i);
     QCborValue takeAt(qsizetype i) { Q_ASSERT(i < size()); return extract(begin() + i); }
@@ -235,7 +236,10 @@ public:
     const_iterator cend() const { return constEnd(); }
     iterator insert(iterator before, const QCborValue &value)
     { insert(before.item.i, value); return iterator{d.data(), before.item.i}; }
+    iterator insert(const_iterator before, const QCborValue &value)
+    { insert(before.item.i, value); return iterator{d.data(), before.item.i}; }
     iterator erase(iterator it) { removeAt(it.item.i); return iterator{d.data(), it.item.i}; }
+    iterator erase(const_iterator it) { removeAt(it.item.i); return iterator{d.data(), it.item.i}; }
 
     void push_back(const QCborValue &t) { append(t); }
     void push_front(const QCborValue &t) { prepend(t); }