Regression - deadlock on undo (eclipse-platform#15)

Reverted commit d610ff2 as it caused
deadlock during undo if the undo operation also wants to use workspace
rule.

This fixes issue
eclipse-platform#15

bundles/org.eclipse.ui.workbench/Eclipse UI/org/eclipse/ui/operations/OperationHistoryActionHandler.java

@@ -21,20 +21,15 @@
 import org.eclipse.core.commands.operations.IUndoContext;
 import org.eclipse.core.commands.operations.IUndoableOperation;
 import org.eclipse.core.commands.operations.OperationHistoryEvent;
-import org.eclipse.core.resources.ResourcesPlugin;
 import org.eclipse.core.runtime.Adapters;
 import org.eclipse.core.runtime.IAdaptable;
 import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.OperationCanceledException;
-import org.eclipse.core.runtime.jobs.IJobManager;
-import org.eclipse.core.runtime.jobs.ISchedulingRule;
-import org.eclipse.core.runtime.jobs.Job;
 import org.eclipse.jface.action.Action;
 import org.eclipse.jface.action.LegacyActionTools;
 import org.eclipse.jface.operation.IRunnableWithProgress;
 import org.eclipse.osgi.util.NLS;
-import org.eclipse.swt.custom.BusyIndicator;
 import org.eclipse.swt.widgets.Display;
 import org.eclipse.swt.widgets.Shell;
 import org.eclipse.ui.IPartListener;
@@ -303,27 +298,7 @@ public final void run() {
 			if (getOperation() instanceof IAdvancedUndoableOperation2) {
 				runInBackground = ((IAdvancedUndoableOperation2) getOperation()).runInBackground();
 			}
-			if (runInBackground) {
-				progressDialog.run(runInBackground, true, runnable);
-			} else {
-				// prevent UI freeze during AutoBuild as in 
-				// org.eclipse.jdt.internal.ui.refactoring.RefactoringExecutionHelper#perform
-				final IJobManager manager = Job.getJobManager();
-				// pessimistic scheduling rule:
-				final ISchedulingRule rule = ResourcesPlugin.getWorkspace().getRoot(); 
-				try {
-					try {
-						// interrupt autobuild or show Wait/Cancel Dialog:
-						Runnable r = () -> manager.beginRule(rule, null);
-						BusyIndicator.showWhile(parent.getDisplay(), r);
-					} catch (OperationCanceledException e) {
-						throw new InterruptedException(e.getMessage());
-					}
-					progressDialog.run(runInBackground, true, runnable); // <-- actual work
-				} finally {
-					manager.endRule(rule);
-				}
-			}
+			progressDialog.run(runInBackground, true, runnable);
 		} catch (InvocationTargetException e) {
 			Throwable t = e.getTargetException();
 			if (t == null) {

bundles/org.eclipse.ui.workbench/META-INF/MANIFEST.MF

@@ -118,8 +118,7 @@ Require-Bundle: org.eclipse.core.runtime;bundle-version="[3.19.0,4.0.0)",
  org.eclipse.emf.ecore;bundle-version="2.7.0",
  org.eclipse.e4.ui.services;bundle-version="1.3.0",
  org.eclipse.emf.ecore.xmi;bundle-version="2.11.0",
- org.eclipse.e4.core.di.extensions;bundle-version="0.13.0",
- org.eclipse.core.resources;bundle-version="3.17.0"
+ org.eclipse.e4.core.di.extensions;bundle-version="0.13.0"
 Import-Package: com.ibm.icu.util,
  javax.annotation,
  javax.inject;version="1.0.0",