Debugger: Disable re-run from application output pane

... for QML engine, which currently does not handle state
transitions in that case.

The normal debug button (or <F5>) of course still work for
starting to debug the current project, which is in most
cases effectively the same.

Change-Id: I02ebf989030a6eb7ff919add6ccc20e7230d9cc1
Reviewed-by: David Schulz <david.schulz@theqtcompany.com>

src/plugins/debugger/debuggerruncontrol.h

@@ -60,6 +60,7 @@ public:
     StopResult stop() override; // Called from SnapshotWindow.
     bool isRunning() const override;
     QString displayName() const override;
+    bool supportsReRunning() const override;
 
     void startFailed();
     void notifyEngineRemoteServerRunning(const QByteArray &msg, int pid);