Description: Fix for the application crashing issue on clicking Remove button twice under "Display Settings". 
 .
 Resolves the following bug - "Click Settings -> Toolbars -> Display Types. Select any Display Type and click Remove button twice. The Application Crashes."
Author: Prathibha B <prathibhab@cdac.in>

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--- avogadro-1.0.3.orig/avogadro/src/mainwindow.cpp
+++ avogadro-1.0.3/avogadro/src/mainwindow.cpp
@@ -3271,6 +3271,7 @@ namespace Avogadro
     if(engine) {
       d->glWidget->removeEngine(engine);
       d->engineSettingsWindows.remove(engine);
+      d->currentSelectedEngine = NULL;
     }
   }