Add a system API to make a package become visible to other package

Expose a system API PackageManager#makeUidVisible for
mainline module to make a package become visible to the caller.

Bug: 222205552
Test: atest AppEnumerationTests
Test: atest PermissionPolicyTest
Ignore-AOSP-First: (for packages/Shell/AndroidManifest.xml) Permission
Change-Id: I6cf322ddfea09a8a4c0c442a6789af4e79d294d7