Debugger: Add Perspective::name() accessor

Will be needed again by GammaRay.

Change-Id: I9afe61dd1db4a1ba4ec95a6abd089e12c6cbcd9a
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/debugger/debuggermainwindow.h

@@ -87,6 +87,7 @@ public:
     void setShouldPersistChecker(const ShouldPersistChecker &checker);
 
     QString id() const; // Currently used by GammaRay plugin.
+    QString name() const;
     QWidget *centralWidget() const;
 
     using Callback = std::function<void()>;