Revert "443680: ATL does not switch perspective automatically when a breakpoint is hit "

This reverts commit 191039ef32c208e38f5072e0161a15495ddd6903.
diff --git a/plugins/org.eclipse.m2m.atl.adt.ui/src/org/eclipse/m2m/atl/adt/ui/AtlUIPlugin.java b/plugins/org.eclipse.m2m.atl.adt.ui/src/org/eclipse/m2m/atl/adt/ui/AtlUIPlugin.java
index 82326d5..dc77682 100644
--- a/plugins/org.eclipse.m2m.atl.adt.ui/src/org/eclipse/m2m/atl/adt/ui/AtlUIPlugin.java
+++ b/plugins/org.eclipse.m2m.atl.adt.ui/src/org/eclipse/m2m/atl/adt/ui/AtlUIPlugin.java
@@ -16,17 +16,10 @@
 import java.util.Map;
 import java.util.MissingResourceException;
 import java.util.ResourceBundle;
-import java.util.logging.Level;
 
 import org.eclipse.core.runtime.Platform;
-import org.eclipse.debug.core.DebugEvent;
-import org.eclipse.debug.core.DebugPlugin;
-import org.eclipse.debug.core.IDebugEventSetListener;
 import org.eclipse.jface.resource.ImageDescriptor;
-import org.eclipse.m2m.atl.common.ATLLogger;
 import org.eclipse.swt.graphics.Image;
-import org.eclipse.ui.PlatformUI;
-import org.eclipse.ui.WorkbenchException;
 import org.eclipse.ui.plugin.AbstractUIPlugin;
 
 /**
@@ -60,35 +53,6 @@
 		} catch (MissingResourceException x) {
 			resourceBundle = null;
 		}
-		addDebugEventListener();
-	}
-
-	/**
-	 * Adds a debug event listener 
-	 */
-	private void addDebugEventListener() {
-		DebugPlugin.getDefault().addDebugEventListener(new IDebugEventSetListener() {
-			public void handleDebugEvents(final DebugEvent[] debugEvents) {
-				for (DebugEvent debugEvent : debugEvents) {
-					if (debugEvent.getKind() == DebugEvent.SUSPEND) {
-						switchToDebugPerspective();
-						break;
-					}
-				}
-			}
-		});
-	}
-
-	/**
-	 * Switches to the debugging perspective.
-	 */
-	private void switchToDebugPerspective() {
-		try {
-			PlatformUI.getWorkbench().showPerspective("org.eclipse.debug.ui.DebugPerspective",
-					PlatformUI.getWorkbench().getActiveWorkbenchWindow());
-		} catch (WorkbenchException e) {
-			ATLLogger.log(Level.SEVERE, e.getMessage(), e);
-		}
 	}
 
 	/**