Fix the -1 unread count bug.

Change-Id: I8b77ad3457504872928c1065d54f50c0618025b5
diff --git a/core/java/android/provider/Gmail.java b/core/java/android/provider/Gmail.java
index 4425e51..157b1c8 100644
--- a/core/java/android/provider/Gmail.java
+++ b/core/java/android/provider/Gmail.java
@@ -1551,7 +1551,7 @@
             if (unreadConversations == null) {
                 return 0;
             } else {
-                return unreadConversations;
+                return unreadConversations < 0 ? 0 : unreadConversations;
             }
         }