DivOverlay: new public method toggle

Refactor Layer\ togglePopup/Tooltip: use common method DivOverlay\toggle

Popup: do not clear map._popup on close as it's redundant

src/layer/DivOverlay.js

@@ -61,6 +61,27 @@ export var DivOverlay = Layer.extend({
 		return this;
 	},
 
+	// @method toggle(layer?: Layer): this
+	// Opens or closes the overlay bound to layer depending on its current state.
+	// Argument may be omitted only for overlay bound to layer.
+	// Alternative to `layer.togglePopup()`/`.toggleTooltip()`.
+	toggle: function (layer) {
+		if (this._map) {
+			this.close();
+		} else {
+			if (arguments.length) {
+				this._source = layer;
+			} else {
+				layer = this._source;
+			}
+			this._prepareOpen();
+
+			// open the overlay on the map
+			this.openOn(layer._map);
+		}
+		return this;
+	},
+
 	onAdd: function (map) {
 		this._zoomAnimated = map._zoomAnimated;
 

src/layer/Popup.js

@@ -140,10 +140,6 @@ export var Popup = DivOverlay.extend({
 	onRemove: function (map) {
 		DivOverlay.prototype.onRemove.call(this, map);
 
-		if (this === map._popup) {
-			map._popup = null;
-		}
-
 		// @namespace Map
 		// @section Popup events
 		// @event popupclose: PopupEvent
@@ -408,11 +404,7 @@ Layer.include({
 	// Opens or closes the popup bound to this layer depending on its current state.
 	togglePopup: function () {
 		if (this._popup) {
-			if (this._popup._map) {
-				this._popup.close();
-			} else {
-				this.openPopup();
-			}
+			this._popup.toggle(this);
 		}
 		return this;
 	},

src/layer/Tooltip.js

@@ -324,11 +324,7 @@ Layer.include({
 	// Opens or closes the tooltip bound to this layer depending on its current state.
 	toggleTooltip: function () {
 		if (this._tooltip) {
-			if (this._tooltip._map) {
-				this._tooltip.close();
-			} else {
-				this.openTooltip();
-			}
+			this._tooltip.toggle(this);
 		}
 		return this;
 	},