Update sandbox structure for apps with sharedUserIds.

For apps with sharedUserIds, sandbox/shared:<shared-user-id> is
currently used as sandbox root. Given that <shared-user-id> can
be upto 255 characters, adding "shared:" might tip over the
filename limit on ext4 filesystems. So, instead use
sandbox/shared/<shared-user-id> as the sandbox root.

Bug: 111890351
Test: manual
Change-Id: Iba437b3eed59f9eb3094a823e8bf2a5a58410fd7
1 file changed