Change names in messaging sample.

Change-Id: I91b971c1c6dd49c320cc41ea08c554a7a4297552
diff --git a/notification/MessagingService/Application/src/main/java/com/example/android/messagingservice/Conversations.java b/notification/MessagingService/Application/src/main/java/com/example/android/messagingservice/Conversations.java
index 210e061..7425df4 100644
--- a/notification/MessagingService/Application/src/main/java/com/example/android/messagingservice/Conversations.java
+++ b/notification/MessagingService/Application/src/main/java/com/example/android/messagingservice/Conversations.java
@@ -45,10 +45,10 @@
      * Senders of the said messages.
      */
     private static final String[] PARTICIPANTS = new String[]{
-            "John Rambo",
-            "Han Solo",
-            "Rocky Balboa",
-            "Lara Croft"
+            "John Smith",
+            "Robert Lawrence",
+            "James Smith",
+            "Jane Doe"
     };
 
     static class Conversation {