Use Qt provided forward declaration header

src/base/search/searchhandler.cpp

@@ -31,6 +31,7 @@
 
 #include <QProcess>
 #include <QTimer>
+#include <QVector>
 
 #include "base/global.h"
 #include "base/utils/foreignapps.h"

src/base/search/searchhandler.h

@@ -33,7 +33,7 @@
 #include <QList>
 #include <QObject>
 #include <QString>
-#include <QVector>
+#include <QtContainerFwd>
 
 class QProcess;
 class QTimer;