Enforce hidden apis usage in product(make)

Only if PRODUCT_ENFORCE_PRODUCT_PARTITION_INTERFACE is set,
every app and java library in product cannot use hidden APIs anymore.

Bug: 132780927
Test: m
Test: set PRODUCT_ENFORCE_PRODUCT_PARTITION_INTERFACE, and check whether build
error occurs.
Change-Id: Ib6c260a16b9cbb95be70d8db3082a15e151687f1
diff --git a/core/soong_config.mk b/core/soong_config.mk
index 1138f08..7ce59f1 100644
--- a/core/soong_config.mk
+++ b/core/soong_config.mk
@@ -197,6 +197,8 @@
   $(call end_json_map))
 $(call end_json_map)
 
+$(call add_json_bool, EnforceProductPartitionInterface,  $(PRODUCT_ENFORCE_PRODUCT_PARTITION_INTERFACE))
+
 $(call json_end)
 
 $(file >$(SOONG_VARIABLES).tmp,$(json_contents))