Tweak SystemUpdatePolicy according to API review.

Make SystemUpdatePolicy Parcelable; hide public constructor and
expose static builder methods.

Bug: 20820025
Change-Id: I594ba3c7e5514551134ba6c866b24498b66506bf
diff --git a/Android.mk b/Android.mk
index 27dedd9..264ad48 100644
--- a/Android.mk
+++ b/Android.mk
@@ -483,6 +483,7 @@
 	frameworks/base/graphics/java/android/graphics/Rect.aidl \
 	frameworks/base/core/java/android/accounts/AuthenticatorDescription.aidl \
 	frameworks/base/core/java/android/accounts/Account.aidl \
+	frameworks/base/core/java/android/app/admin/SystemUpdatePolicy.aidl \
 	frameworks/base/core/java/android/print/PrintDocumentInfo.aidl \
 	frameworks/base/core/java/android/print/PageRange.aidl \
 	frameworks/base/core/java/android/print/PrintAttributes.aidl \