Index: trunk/test/unit/org/openstreetmap/josm/io/NoteImporterTest.java
===================================================================
--- trunk/test/unit/org/openstreetmap/josm/io/NoteImporterTest.java	(revision 10414)
+++ trunk/test/unit/org/openstreetmap/josm/io/NoteImporterTest.java	(revision 10432)
@@ -7,8 +7,9 @@
 import java.io.File;
 
+import org.junit.Rule;
 import org.junit.Test;
 import org.openstreetmap.josm.Main;
 import org.openstreetmap.josm.TestUtils;
-import org.openstreetmap.josm.gui.layer.Layer;
+import org.openstreetmap.josm.testutils.JOSMTestRules;
 
 /**
@@ -18,14 +19,15 @@
 
     /**
+     * Use the test rules to remove any layers and reset state.
+     */
+    @Rule
+    public final JOSMTestRules rules = new JOSMTestRules();
+
+    /**
      * Non-regression test for <a href="https://josm.openstreetmap.de/ticket/12531">Bug #12531</a>.
      */
     @Test
     public void testTicket12531() {
-        if (Main.map != null) {
-            for (Layer l: Main.getLayerManager().getLayers()) {
-                Main.getLayerManager().removeLayer(l);
-            }
-            Main.main.setMapFrame(null);
-        }
+        Main.getLayerManager().resetState();
         assertNull(Main.map);
         assertTrue(new NoteImporter().importDataHandleExceptions(
Index: trunk/test/unit/org/openstreetmap/josm/testutils/JOSMTestRules.java
===================================================================
--- trunk/test/unit/org/openstreetmap/josm/testutils/JOSMTestRules.java	(revision 10414)
+++ trunk/test/unit/org/openstreetmap/josm/testutils/JOSMTestRules.java	(revision 10432)
@@ -13,5 +13,4 @@
 import org.openstreetmap.josm.Main;
 import org.openstreetmap.josm.data.projection.Projections;
-import org.openstreetmap.josm.gui.layer.MainLayerManager;
 import org.openstreetmap.josm.gui.util.GuiHelper;
 import org.openstreetmap.josm.io.OsmApi;
@@ -223,8 +222,5 @@
         });
         // Remove all layers
-        MainLayerManager lm = Main.getLayerManager();
-        while (!lm.getLayers().isEmpty()) {
-            lm.removeLayer(lm.getLayers().get(0));
-        }
+        Main.getLayerManager().resetState();
 
         // TODO: Remove global listeners and other global state.