NPE in SpellcheckableMessageArea$1.widgetDisposed when closing Eclipse

Allow to use a local service locator for retrieving IHandlerService.
Use the workbench window's service locator if the local is not available
e.g. in a dialog.

Bug: 381052
Change-Id: Ie953df8983bf0fd28496feb886ca4e1ae7201b9f
Signed-off-by: Robin Stocker <robin@nibor.org>

2 files changed, 16 insertions, 4 deletions

diff --git a/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/dialogs/SpellcheckableMessageArea.java b/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/dialogs/SpellcheckableMessageArea.java
index 11bb704a0c..0a40adfced 100644
--- a/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/dialogs/SpellcheckableMessageArea.java
+++ b/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/dialogs/SpellcheckableMessageArea.java
@@ -614,10 +614,18 @@ public class SpellcheckableMessageArea extends Composite {
 		};
 	}
 
-	private IHandlerService getHandlerService() {
-		final IHandlerService handlerService = (IHandlerService) PlatformUI
-		.getWorkbench().getService(IHandlerService.class);
-		return handlerService;
+	/**
+	 * Return <code>IHandlerService</code>. The default implementation uses the
+	 * workbench window's service locator. Subclasses may override to access the
+	 * service by using a local service locator.
+	 *
+	 * @return <code>IHandlerService</code> using the workbench window's service
+	 *         locator. Can be <code>null</code> if the service could not be
+	 *         found.
+	 */
+	protected IHandlerService getHandlerService() {
+		return (IHandlerService) PlatformUI.getWorkbench().getService(
+				IHandlerService.class);
 	}
 
 	private SourceViewerDecorationSupport configureAnnotationPreferences() {
diff --git a/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/staging/StagingView.java b/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/staging/StagingView.java
index ff7d8cfd71..927a53c748 100644
--- a/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/staging/StagingView.java
+++ b/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/staging/StagingView.java
@@ -405,6 +405,10 @@ public class StagingView extends ViewPart {
 			protected CommitProposalProcessor getCommitProposalProcessor() {
 				return commitProposalProcessor;
 			}
+			@Override
+			protected IHandlerService getHandlerService() {
+				return (IHandlerService) getSite().getService(IHandlerService.class);
+			}
 		};
 		commitMessageText.setData(FormToolkit.KEY_DRAW_BORDER,
 				FormToolkit.TEXT_BORDER);