title: FIRMessaging Delegate Error
body: <p>I tried to add FIRMessagingDelegate but Xcode gives an error </p>
  
  <p><code>Cannot find protocol declaration for FIRMessagingDelegate.</code> </p>
  
  <p>I imported FirebaseMessaging and it gives no errors. I checked pods and it seems fine.</p>
  
  <pre><code>Installing Firebase (3.2.1)
  Using FirebaseAnalytics (3.2.0)
  Using FirebaseInstanceID (1.0.6)
  Installing FirebaseMessaging (1.1.0)
  </code></pre>
  
  <p>How I try to implement;</p>
  
  <pre><code>#import &lt;UIKit/UIKit.h&gt;
  #import &lt;UserNotifications/UserNotifications.h&gt;
  #import &lt;MessageUI/MessageUI.h&gt;
  
  #if defined(__IPHONE_10_0) &amp;&amp; __IPHONE_OS_VERSION_MAX_ALLOWED &gt;= __IPHONE_10_0
  @import UserNotifications;
  #endif
  
  @import Firebase;
  @import FirebaseInstanceID;
  @import FirebaseMessaging;
  
  @interface AppDelegate : UIResponder &lt;UIApplicationDelegate, UNUserNotificationCenterDelegate, FIRMessagingDelegate&gt;
  </code></pre>
  
  <p>I could not find any solution, what could be the reason for error?</p>