Add tests for the XPC client.

chrome/browser/notifications/stub_alert_dispatcher_mac.h

Index: chrome/browser/notifications/stub_alert_dispatcher_mac.h
diff --git a/chrome/browser/notifications/stub_alert_dispatcher_mac.h b/chrome/browser/notifications/stub_alert_dispatcher_mac.h
new file mode 100644
index 0000000000000000000000000000000000000000..eb51803644fecc57f23496897a307a91a166334e
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+++ b/chrome/browser/notifications/stub_alert_dispatcher_mac.h
@@ -0,0 +1,26 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_NOTIFICATIONS_STUB_ALERT_DISPATCHER_
+#define CHROME_BROWSER_NOTIFICATIONS_STUB_ALERT_DISPATCHER_
+
+#import <Foundation/Foundation.h>
+
+#import "chrome/browser/notifications/alert_dispatcher_mac.h"
+
+@interface StubAlertDispatcher : NSObject<AlertDispatcher>
+
+- (void)dispatchNotification:(NSDictionary*)data;
+
+- (void)closeNotificationWithId:(NSString*)notificationId
+                  withProfileId:(NSString*)profileId;
+
+- (void)closeAllNotifications;
+
+// Stub specific methods.
+- (NSArray*)alerts;
+
+@end
+
+#endif  // CHROME_BROWSER_NOTIFICATIONS_STUB_ALERT_DISPATCHER_