JsonWizard: Enable validators for lineedits on Fields pages

Make use of a validator when entering C++ class names.

Change-Id: Id7f9c8c2e1fe036397a337595cbe7aa7fd9589d5
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@theqtcompany.com>

src/plugins/projectexplorer/jsonwizard/jsonfieldpage.h

@@ -40,6 +40,7 @@ QT_BEGIN_NAMESPACE
 class QFormLayout;
 class QLabel;
 class QLineEdit;
+class QRegularExpression;
 class QTextEdit;
 QT_END_NAMESPACE
 
@@ -127,6 +128,7 @@ public:
     {
     public:
         LineEditField();
+        ~LineEditField();
 
     private:
         bool parseData(const QVariant &data, QString *errorMessage);
@@ -140,6 +142,7 @@ public:
         QString m_placeholderText;
         QString m_defaultText;
         QString m_disabledText;
+        QRegularExpression *m_validatorRegExp;
 
         bool m_isModified;
         mutable QString m_currentText;