Explicitly export content providers

In a future version of Android, the default value for
<provider android:exported> will change from true to false.
Explicitly set android:exported="true"

Bug: 3306452
Change-Id: Ic569a8b6d8d123b6606afe0e01cf506211cc6694
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 3a37acf..2e78f78 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -26,6 +26,7 @@
         >
         <provider android:name="UserDictionaryProvider" android:authorities="user_dictionary"
                 android:syncable="false" android:multiprocess="false"
+                android:exported="true"
                 android:readPermission="android.permission.READ_USER_DICTIONARY" 
                 android:writePermission="android.permission.WRITE_USER_DICTIONARY" />
     </application>