More robust and efficient handling of unload request.

1) it broke when state has changed on same view
2) no need to perform full buildView, only createView with
restoreViewScopeState is sufficient and faster

src/main/java/org/omnifaces/cdi/viewscope/ViewScopeManager.java

@@ -190,6 +190,12 @@ private int getMaxActiveViewScopes() {
 	 * CDI bean storage will also be auto-created.
 	 */
 	private UUID getBeanStorageId(boolean create) {
+		FacesContext context = FacesContext.getCurrentInstance();
+
+		if (isUnloadRequest(context)) {
+			return UUID.fromString(getRequestParameter(context, "id"));
+		}
+
 		UUID id = getViewAttribute(ViewScopeManager.class.getName());
 
 		if (id == null || activeViewScopes.get(id) == null) {
@@ -205,6 +211,9 @@ private UUID getBeanStorageId(boolean create) {
 		return id;
 	}
 
+	/**
+	 * Create CDI bean storage and register unload script.
+	 */
 	private void createViewScope(UUID id) {
 		activeViewScopes.put(id, new BeanStorage(DEFAULT_BEANS_PER_VIEW_SCOPE));
 
@@ -217,7 +226,7 @@ else if (!Hacks.isScriptResourceRendered(context, new ResourceIdentifier("omnifa
 			addScriptResourceToBody("omnifaces", "unload.js");
 		}
 
-		addScriptToBody("OmniFaces.Unload.init()");
+		addScriptToBody("OmniFaces.Unload.init('" + id + "')");
 	}
 
 	/**

src/main/java/org/omnifaces/viewhandler/RestorableViewHandler.java

@@ -74,9 +74,10 @@ public RestorableViewHandler(ViewHandler wrapped) {
 	 */
 	@Override
 	public UIViewRoot restoreView(FacesContext context, String viewId) {
-		if (isUnloadRequest(context) && getRenderKit(context).getResponseStateManager().getState(context, viewId) == null) {
-			context.responseComplete();
-			return new UIViewRoot();
+		if (isUnloadRequest(context)) {
+			UIViewRoot createdView = createView(context, viewId);
+			createdView.restoreViewScopeState(context, getRenderKit(context).getResponseStateManager().getState(context, viewId));
+			return createdView;
 		}
 
 		UIViewRoot restoredView = super.restoreView(context, viewId);
@@ -85,27 +86,23 @@ public UIViewRoot restoreView(FacesContext context, String viewId) {
 			return restoredView;
 		}
 
-		UIViewRoot createdView;
-
 		try {
-			createdView = buildView(viewId);
+			UIViewRoot createdView = buildView(viewId);
+			return isRestorableView(createdView) ? createdView : null;
 		}
 		catch (IOException e) {
 			throw new FacesException(e);
 		}
-
-		if (TRUE.equals(createdView.getAttributes().get(EnableRestorableView.class.getName()))) {
-			return createdView;
-		}
-		else {
-			return null;
-		}
 	}
 
 	private boolean isRestorableViewEnabled(FacesContext context) {
 		return TRUE.equals(getApplicationAttribute(context, EnableRestorableView.class.getName()));
 	}
 
+	private boolean isRestorableView(UIViewRoot view) {
+		return TRUE.equals(view.getAttributes().get(EnableRestorableView.class.getName()));
+	}
+
 	@Override
 	public ViewHandler getWrapped() {
 		return wrapped;

src/main/resources/META-INF/resources/omnifaces/unload.unminified.js

@@ -32,7 +32,7 @@ OmniFaces.Unload = (function() {
 	/**
 	 * Initialize the "unload" event listener on the current document.
 	 */
-	unload.init = function() {
+	unload.init = function(id) {
 		if (!window.XMLHttpRequest) {
 			return; // Native XHR not supported (IE6/7 not supported). End of story. Let session expiration do its job.
 		}
@@ -53,7 +53,7 @@ OmniFaces.Unload = (function() {
 				var xhr = new XMLHttpRequest();
 				xhr.open("POST", window.location.href.split(/[?#;]/)[0], false);
 				xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
-				xhr.send("omnifaces.event=unload&" + VIEW_STATE_PARAM + "=" + viewState);
+				xhr.send("omnifaces.event=unload&id=" + id + "&" + VIEW_STATE_PARAM + "=" + viewState);
 			}
 			catch (e) {
 				// Fail silently. You never know.