Debugger: add <load more> functionality to array dumper

Change-Id: Ib44748fa3218788ca20a99b0a0f4cd85716dde06
Reviewed-by: hjk <hjk@qt.io>

src/plugins/debugger/watchhandler.h

@@ -60,6 +60,7 @@ public:
 
     bool isExpandedIName(const QString &iname) const;
     QSet<QString> expandedINames() const;
+    int maxArrayCount(const QString &iname) const;
 
     static QStringList watchedExpressions();
     static QMap<QString, int> watcherNames();