Add test package for MTPDocumentsProvider.

BUG=20274999

Change-Id: I179692d3b14392a0634d4c0ace21a9d96a2d0d6a
diff --git a/packages/MtpDocumentsProvider/AndroidManifest.xml b/packages/MtpDocumentsProvider/AndroidManifest.xml
index 9a1dc36..6172354 100644
--- a/packages/MtpDocumentsProvider/AndroidManifest.xml
+++ b/packages/MtpDocumentsProvider/AndroidManifest.xml
@@ -1,3 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
           package="com.android.mtp"
           android:sharedUserId="android.media">