Add two (forgotten) since 5.0

SHA for QWidget::hasHeightForWidth change:
466107107a

SHA for QAbstractItemDelegate::destoryeditor change
15f253a46a

Change-Id: Ic7e38c15f62eef22ab95414fad6e7b6c9c7d4f59
Reviewed-by: Girish Ramakrishnan <girish.1.ramakrishnan@nokia.com>
Reviewed-by: Stephen Kelly <stephen.kelly@kdab.com>

src/widgets/itemviews/qabstractitemdelegate.cpp

@@ -243,6 +243,8 @@ QWidget *QAbstractItemDelegate::createEditor(QWidget *,
 
 
 /*!
+    \since 5.0
+
     A function called when the editor is no longer needed and should be
     destroyed. The default behavior is a call to deleteLater on the editor.
     It possible e.g. to avoid this delete by reimplementing this function.

src/widgets/kernel/qwidget.cpp

@@ -9228,6 +9228,8 @@ int QWidget::heightForWidth(int w) const
 
 
 /*!
+    \Since 5.0
+
     Returns true if the widget's preferred height depends on its width; otherwise returns false.
 */ 
 bool QWidget::hasHeightForWidth() const