Export PRODUCT_SOONG_NAMESPACES to Soong

Bug: 65683273
Test: put 'PRODUCT_SOONG_NAMESPACES := jeff-test/dir1' \
      in a .mk file and observe its value copied into \
      out/soong/soong.variables

Change-Id: I2b61caa46f40f35ccecf64da88918b73180e02e8

core/product.mk

@@ -102,6 +102,7 @@ _product_var_list := \
     PRODUCT_SDK_ADDON_COPY_MODULES \
     PRODUCT_SDK_ADDON_DOC_MODULES \
     PRODUCT_SDK_ADDON_SYS_IMG_SOURCE_PROP \
+    PRODUCT_SOONG_NAMESPACES \
     PRODUCT_DEFAULT_WIFI_CHANNELS \
     PRODUCT_DEFAULT_DEV_CERTIFICATE \
     PRODUCT_RESTRICT_VENDOR_FILES \

core/product_config.mk

@@ -480,3 +480,7 @@ PRODUCT_CFI_EXCLUDE_PATHS := \
 # Whether any paths should have CFI enabled for components
 PRODUCT_CFI_INCLUDE_PATHS := \
     $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_CFI_INCLUDE_PATHS))
+
+# which Soong namespaces to export to Make
+PRODUCT_SOONG_NAMESPACES :=
+    $(strip $(PRODUCTS.$(INTERNAL_PRODUCT).PRODUCT_SOONG_NAMESPACES))

core/soong_config.mk

@@ -121,6 +121,8 @@ $(call add_json_bool, UseGoma,                           $(filter-out false,$(US
 
 $(call add_json_str,  DistDir,                           $(if $(dist_goal), $(DIST_DIR)))
 
+$(call add_json_list, NamespacesToExport,                $(PRODUCT_SOONG_NAMESPACES))
+
 _contents := $(subst $(comma)$(newline)__SV_END,$(newline)}$(newline),$(_contents)__SV_END)
 
 $(file >$(SOONG_VARIABLES).tmp,$(_contents))