Debugger: Modernize

modernize-use-auto
modernize-use-nullptr
modernize-use-override
modernize-use-using
modernize-use-default-member-init
modernize-use-equals-default

Change-Id: I91a6874f0d7b94e9079ab4ef07c23c60c80be9c0
Reviewed-by: Christian Stenger <christian.stenger@qt.io>
Reviewed-by: hjk <hjk@qt.io>

src/plugins/debugger/watchwindow.cpp

@@ -41,7 +41,7 @@ namespace Debugger {
 namespace Internal {
 
 WatchTreeView::WatchTreeView(WatchType type)
-  : m_type(type), m_sliderPosition(0)
+  : m_type(type)
 {
     setObjectName("WatchWindow");
     setWindowTitle(tr("Locals and Expressions"));