Add BUILD_PRE_S_APEX to conditionally generate pre-S apex.

Used in CI and BUILD_PRE_S_APEX passed in via command line arguments.
default=false, to prevent presubmit run-time regression.

Ignore-AOSP-First: Will cherrypick into AOSP once tm-mlp is done.
BUG: 198437211
BUG: 235701311
Test: TH and local build.
Change-Id: Iae29c0c7119ec2cfc641e346280bd60f861b8ae1

build/build_unbundled_mainline_module.sh

@@ -110,12 +110,13 @@ function init() {
     exit 1
   fi
 
-  declare -grx DIST_DIR="${dist_dir}"
+  DIST_DIR="${dist_dir}"
   declare -grx TARGET_BUILD_APPS="${TARGET_BUILD_APPS:-${DEFAULT_MODULES[*]}}"
   declare -grx TARGET_BUILD_DENSITY="${TARGET_BUILD_DENSITY:-alldpi}"
   declare -grx TARGET_BUILD_TYPE="${TARGET_BUILD_TYPE:-release}"
   declare -grx TARGET_BUILD_VARIANT="${TARGET_BUILD_VARIANT:-user}"
   declare -grx TARGET_PRODUCT="${product}"
+  declare -grx BUILD_PRE_S_APEX="${BUILD_PRE_S_APEX:-false}"
 
   # This script cannot handle compressed apexes
   declare -grx OVERRIDE_PRODUCT_COMPRESSED_APEX=false
@@ -125,6 +126,18 @@ function init() {
   # frameworks/base).
 }
 
+function build_modules() {
+
+  build/soong/soong_ui.bash --make-mode "$@" \
+    ALWAYS_EMBED_NOTICES=true \
+    MODULE_BUILD_FROM_SOURCE=true \
+    ${extra_build_params} \
+    "${RUN_ERROR_PRONE:+"RUN_ERROR_PRONE=true"}" \
+    apps_only \
+    dist \
+    lint-check
+}
+
 function main() {
   if [ ! -e "build/make/core/Makefile" ]; then
     echo "$0 must be run from the top of the Android source tree."
@@ -135,13 +148,18 @@ function main() {
   # the buildbots.
   build/soong/soong_ui.bash --make-mode installclean
 
-  build/soong/soong_ui.bash --make-mode "$@" \
+  DIST_DIR="${DIST_DIR}" build_modules
-    ALWAYS_EMBED_NOTICES=true \
+
-    MODULE_BUILD_FROM_SOURCE=true \
+  # TODO(b/198437211): remove unconditionally added APEX_BUILD_FOR_PRE_S_DEVICES
-    "${RUN_ERROR_PRONE:+"RUN_ERROR_PRONE=true"}" \
+  # below.
-    apps_only \
+  # Command line flag passed in would also build modules configured
-    dist \
+  # for PRE_S configuration.  Disabled by default, this feature enables
-    lint-check
+  # building modules with statically linked libraries.
+  # https://goto.google.com/building-dynamic-common-apex-variants
+  # Artifacts are stored in a different dist_dir (*_pre_s)
+  if [[ "${BUILD_PRE_S_APEX}" == "true" ]]; then
+      DIST_DIR="${DIST_DIR}_pre_s" APEX_BUILD_FOR_PRE_S_DEVICES=true build_modules
+  fi
 }
 
 init "$@"