Adding shell commands for grant/revoke of bind app widget permisison.

Testing the app widget APIs requires binding of widgets which is guarded
by a system signature permission or white listing. Since CTS tests can
not be signed with the platform certificate, they should be able to
temporariliy white list their package. This command adds the ability to
grant and revoke the provilege to bind app widgets to a given package.

Change-Id: I6de1bbf27ac684ec47e61157f19ec6d29e2db979
diff --git a/packages/Shell/AndroidManifest.xml b/packages/Shell/AndroidManifest.xml
index 56f5a3a..6f41565 100644
--- a/packages/Shell/AndroidManifest.xml
+++ b/packages/Shell/AndroidManifest.xml
@@ -89,6 +89,7 @@
     <uses-permission android:name="android.permission.GET_ACCOUNTS" />
     <uses-permission android:name="android.permission.RETRIEVE_WINDOW_TOKEN" />
     <uses-permission android:name="android.permission.FRAME_STATS" />
+    <uses-permission android:name="android.permission.BIND_APPWIDGET" />
 
     <application android:label="@string/app_label">
         <provider