Close SubmoduleWalk in RepositoriesViewContentProvider

Change-Id: If01f7682057397f4829b5ea4760ef2e76f188d40
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>
diff --git a/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/repository/RepositoriesViewContentProvider.java b/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/repository/RepositoriesViewContentProvider.java
index 0fb5171..f50a9b7 100644
--- a/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/repository/RepositoriesViewContentProvider.java
+++ b/org.eclipse.egit.ui/src/org/eclipse/egit/ui/internal/repository/RepositoriesViewContentProvider.java
@@ -335,9 +335,8 @@
 
 		case SUBMODULES:
 			List<RepositoryNode> children = new ArrayList<>();
-			try {
-				SubmoduleWalk walk = SubmoduleWalk.forIndex(node
-						.getRepository());
+			try (SubmoduleWalk walk = SubmoduleWalk
+					.forIndex(node.getRepository())) {
 				while (walk.next()) {
 					Repository subRepo = walk.getRepository();
 					if (subRepo != null) {