Implement directed recovery snapshot.

Bug: 177451657
Test: m -j nothing
Change-Id: I902afe71e7577c1c41371f1422512170edf6e492
diff --git a/core/soong_config.mk b/core/soong_config.mk
index fd8d3e4..bdc8ce9 100644
--- a/core/soong_config.mk
+++ b/core/soong_config.mk
@@ -153,6 +153,12 @@
   $(call add_json_bool,$(module),true))
 $(call end_json_map)
 
+$(call add_json_bool, DirectedRecoverySnapshot,          $(DIRECTED_RECOVERY_SNAPSHOT))
+$(call add_json_map,  RecoverySnapshotModules)
+$(foreach module,$(RECOVERY_SNAPSHOT_MODULES),\
+  $(call add_json_bool,$(module),true))
+$(call end_json_map)
+
 $(call add_json_bool, Treble_linker_namespaces,          $(filter true,$(PRODUCT_TREBLE_LINKER_NAMESPACES)))
 $(call add_json_bool, Enforce_vintf_manifest,            $(filter true,$(PRODUCT_ENFORCE_VINTF_MANIFEST)))