Fix FIAM API Definition (#1873)

Author: JasonAHeron

firebase-inappmessaging/api.txt

@@ -4,6 +4,8 @@ package com.google.firebase.inappmessaging {
   public class FirebaseInAppMessaging {
     method public void addClickListener(@NonNull com.google.firebase.inappmessaging.FirebaseInAppMessagingClickListener);
     method public void addClickListener(@NonNull com.google.firebase.inappmessaging.FirebaseInAppMessagingClickListener, @NonNull java.util.concurrent.Executor);
+    method public void addDismissListener(@NonNull com.google.firebase.inappmessaging.FirebaseInAppMessagingDismissListener);
+    method public void addDismissListener(@NonNull com.google.firebase.inappmessaging.FirebaseInAppMessagingDismissListener, @NonNull java.util.concurrent.Executor);
     method public void addDisplayErrorListener(@NonNull com.google.firebase.inappmessaging.FirebaseInAppMessagingDisplayErrorListener);
     method public void addDisplayErrorListener(@NonNull com.google.firebase.inappmessaging.FirebaseInAppMessagingDisplayErrorListener, @NonNull java.util.concurrent.Executor);
     method public void addImpressionListener(@NonNull com.google.firebase.inappmessaging.FirebaseInAppMessagingImpressionListener);
@@ -30,6 +32,10 @@ package com.google.firebase.inappmessaging {
     method @NonNull public String getTriggerName();
   }
 
+  public interface FirebaseInAppMessagingDismissListener {
+    method public void messageDismissed(@NonNull com.google.firebase.inappmessaging.model.InAppMessage);
+  }
+
   @Keep public interface FirebaseInAppMessagingDisplay {
     method @Keep public void displayMessage(@NonNull com.google.firebase.inappmessaging.model.InAppMessage, @NonNull com.google.firebase.inappmessaging.FirebaseInAppMessagingDisplayCallbacks);
   }