soong: Add `aapt_version_code` default

This appends  to aapt flags, which is
useful for flushing some caches upon system updates.

Change-Id: I4ae1a1939f97f9ce6bb821b0b5687ad48e8ea343
diff --git a/build/soong/Android.bp b/build/soong/Android.bp
index bded9c0..e83fdb9 100644
--- a/build/soong/Android.bp
+++ b/build/soong/Android.bp
@@ -51,6 +51,26 @@
 
 // Target platform agnostic config modules
 soong_config_module_type {
+    name: "aapt_version_code",
+    module_type: "java_defaults",
+    config_namespace: "blissGlobalVars",
+    value_variables: ["aapt_version_code"],
+    properties: ["aaptflags"],
+}
+
+aapt_version_code {
+    name: "aapt_version_code_defaults",
+    soong_config_variables: {
+        aapt_version_code: {
+            aaptflags: [
+                "--version-code",
+                "%s",
+            ],
+        },
+    },
+}
+
+soong_config_module_type {
     name: "gralloc_10_usage_bits",
     module_type: "cc_defaults",
     config_namespace: "blissGlobalVars",
diff --git a/config/BoardConfigSoong.mk b/config/BoardConfigSoong.mk
index 9a11299..afe1932 100644
--- a/config/BoardConfigSoong.mk
+++ b/config/BoardConfigSoong.mk
@@ -28,6 +28,7 @@
 
 SOONG_CONFIG_NAMESPACES += blissGlobalVars
 SOONG_CONFIG_blissGlobalVars += \
+    aapt_version_code \
     additional_gralloc_10_usage_bits \
     camera_needs_client_info \
     target_init_vendor_lib \
@@ -80,6 +81,7 @@
 TARGET_SURFACEFLINGER_UDFPS_LIB ?= surfaceflinger_udfps_lib
 
 # Soong value variables
+SOONG_CONFIG_blissGlobalVars_aapt_version_code := $(shell date -u +%Y%m%d)
 SOONG_CONFIG_blissGlobalVars_additional_gralloc_10_usage_bits := $(TARGET_ADDITIONAL_GRALLOC_10_USAGE_BITS)
 SOONG_CONFIG_blissGlobalVars_target_init_vendor_lib := $(TARGET_INIT_VENDOR_LIB)
 SOONG_CONFIG_blissGlobalVars_target_ld_shim_libs := $(subst $(space),:,$(TARGET_LD_SHIM_LIBS))