Fix ADT Build. ExplodedRenderingHelperTest was not updated to the new API of ExplodedRenderingHelper

Change-Id: I987004d3869f9e2f94efb0bec1f92f55a8c42501
diff --git a/eclipse/plugins/com.android.ide.eclipse.tests/unittests/com/android/ide/eclipse/adt/internal/editors/layout/ExplodeRenderingHelperTest.java b/eclipse/plugins/com.android.ide.eclipse.tests/unittests/com/android/ide/eclipse/adt/internal/editors/layout/ExplodeRenderingHelperTest.java
index 690bd22..516cb04 100644
--- a/eclipse/plugins/com.android.ide.eclipse.tests/unittests/com/android/ide/eclipse/adt/internal/editors/layout/ExplodeRenderingHelperTest.java
+++ b/eclipse/plugins/com.android.ide.eclipse.tests/unittests/com/android/ide/eclipse/adt/internal/editors/layout/ExplodeRenderingHelperTest.java
@@ -21,14 +21,13 @@
 
 import org.w3c.dom.Node;
 
-import java.util.ArrayList;
-import java.util.List;
+import java.util.HashSet;
 
 import junit.framework.TestCase;
 
 public class ExplodeRenderingHelperTest extends TestCase {
 
-    private final List<String> mLayoutNames = new ArrayList<String>();
+    private final HashSet<String> mLayoutNames = new HashSet<String>();
 
     @Override
     protected void setUp() throws Exception {