Allow installd to link apk_data_file and dalvikcache_data_file.

Needed for split app installs, where we link existing apks and
compiled output to the stage location.

bug: 20889739

Change-Id: I610dc5b12cb46b03894002d60db7c06412d12cab

installd.te

@@ -8,11 +8,11 @@ allow installd self:capability { chown dac_override fowner fsetid setgid setuid
 
 # Allow labeling of files under /data/app/com.example/oat/
 allow installd dalvikcache_data_file:dir relabelto;
-allow installd dalvikcache_data_file:file relabelto;
+allow installd dalvikcache_data_file:file { relabelto link };
 
 # Allow movement of APK files between volumes
 allow installd apk_data_file:dir { create_dir_perms relabelfrom };
-allow installd apk_data_file:file { create_file_perms relabelfrom };
+allow installd apk_data_file:file { create_file_perms relabelfrom link };
 allow installd apk_data_file:lnk_file { create read unlink };
 
 allow installd asec_apk_file:file r_file_perms;