Add KeyChain Test API for the credential manager

* Add setCredentialManagementApp and
  removeCredentialManagementApp
  to KeyChain
* Add permission to manage credential
  management app, which is to be used in
  CTS tests

Bug: 165641221
Test: atest android.devicepolicy.cts.CredentialManagementAppTest
Change-Id: I8487ebc13758a31639d55c8e380faa51d1cfd843
diff --git a/packages/Shell/AndroidManifest.xml b/packages/Shell/AndroidManifest.xml
index f83f670..d221819 100644
--- a/packages/Shell/AndroidManifest.xml
+++ b/packages/Shell/AndroidManifest.xml
@@ -119,6 +119,7 @@
     <uses-permission android:name="android.permission.INTERACT_ACROSS_USERS" />
     <uses-permission android:name="android.permission.INTERACT_ACROSS_USERS_FULL" />
     <uses-permission android:name="android.permission.CREATE_USERS" />
+    <uses-permission android:name="android.permission.MANAGE_CREDENTIAL_MANAGEMENT_APP" />
     <uses-permission android:name="android.permission.MANAGE_DEVICE_ADMINS" />
     <uses-permission android:name="android.permission.ACCESS_LOWPAN_STATE"/>
     <uses-permission android:name="android.permission.CHANGE_LOWPAN_STATE"/>