Add fake host snapshot support

Map HOST_FAKE_SNAPSHOT_ENABLE to HostFakeSnapshotEnabled() method.

Bug: 194799048
Test: m HOST_FAKE_SNAPSHOT_ENABLE=true host-fake-snapshot dist -- check snapshot exists in dist

Change-Id: Idd343c3dec3cc24514a5d587b06c3b1300598b7d
diff --git a/core/soong_config.mk b/core/soong_config.mk
index d3f983c..9d1dc98 100644
--- a/core/soong_config.mk
+++ b/core/soong_config.mk
@@ -163,6 +163,7 @@
 $(call add_json_list, VendorSnapshotDirsExcluded,        $(VENDOR_SNAPSHOT_DIRS_EXCLUDED))
 $(call add_json_list, RecoverySnapshotDirsIncluded,      $(RECOVERY_SNAPSHOT_DIRS_INCLUDED))
 $(call add_json_list, RecoverySnapshotDirsExcluded,      $(RECOVERY_SNAPSHOT_DIRS_EXCLUDED))
+$(call add_json_bool, HostFakeSnapshotEnabled,           $(HOST_FAKE_SNAPSHOT_ENABLE))
 
 $(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)))