Integrate Controller w/ AttachmentDownloadService

* Add ControllerService to Controller and call this from
  AttachmentDownloadService to handle attachment loading

(It's a redo of I3a6c2a40.  Submitting for mlbank, who had a trouble
with repo.)

Change-Id: I7c90761ec4e213d6dc331fc894c7b77e84ad43a6
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 305e36a..31863e3 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -278,8 +278,8 @@
         </service>
 
         <service
-            android:name=".Controller"
-            android:enabled="false"
+            android:name=".Controller$ControllerService"
+            android:enabled="true"
             >
         </service>