Bug fix + test for 6dc3

spec/suites/removeLayersSpec.js

@@ -57,6 +57,9 @@
 
 		markers[0].__parent.spiderfy();
 
+		// We must wait for the spiderfy animation to timeout
+		clock.tick(200);
+
 		group.removeLayers(markers);
 
 		expect(group.hasLayer(markers[0])).to.be(false);
@@ -64,5 +67,9 @@
 		expect(group.hasLayer(markers[2])).to.be(false);
 
 		expect(group.getLayers().length).to.be(0);
+
+		group.on('spiderfied', function() {
+			expect(group._spiderfied).to.be(null);
+		});
 	});
 });

src/MarkerClusterGroup.js

@@ -251,6 +251,10 @@ L.MarkerClusterGroup = L.FeatureGroup.extend({
 			fg = this._featureGroup,
 			npg = this._nonPointGroup;
 
+		if (this._unspiderfy) {
+			this._unspiderfy();
+		}
+
 		if (!this._map) {
 			for (i = 0, l = layersArray.length; i < l; i++) {
 				m = layersArray[i];