Increment Exchange version.

Change-Id: I43a7757da98d0b9dca7310ef0c4efaa35de86fea
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 98fc087..bccd96b 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -17,7 +17,7 @@
 <manifest
     xmlns:android="http://schemas.android.com/apk/res/android"
     package="com.android.exchange"
-    android:versionCode="500050" >
+    android:versionCode="500051" >
 
     <uses-permission
         android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>