QKeySequenceEdit: give nested line edit an objectName

People request this, and other widgets do this, too (say, QSpinBox).

Change-Id: I275537fb82b805b0dcb8edba87b8e234985f8d1f
Reviewed-by: J-P Nurmi <jpnurmi@digia.com>

src/widgets/widgets/qkeysequenceedit.cpp

@@ -55,6 +55,7 @@ void QKeySequenceEditPrivate::init()
     Q_Q(QKeySequenceEdit);
 
     lineEdit = new QLineEdit(q);
+    lineEdit->setObjectName(QStringLiteral("qt_keysequenceedit_lineedit"));
     keyNum = 0;
     prevKey = -1;
     releaseTimer = 0;