Add BUILD_BROKEN_DONT_CHECK_SYSTEMSDK

https://android-review.git.corp.google.com/q/topic:limit_systemsdk
introduced a new check for preventing the use of system SDKs above 34
from Java modules in the vendor partition.

As this may break some unprepared targets, introduce
BUILD_BROKEN_DONT_CHECK_SYSTEMSDK as a temporary escape hatch.

This flag will be deleted eventually.

Bug: 314011075
Test: Add BUILD_BROKEN_DONT_CHECK_SYSTEMSDK := true to BoardConfig.mk
Change-Id: Ie70ce428ec3df8580099efd99e5c7c9c4f9daecb
diff --git a/core/board_config.mk b/core/board_config.mk
index ae11eb6..5a1a781 100644
--- a/core/board_config.mk
+++ b/core/board_config.mk
@@ -186,6 +186,7 @@
   BUILD_BROKEN_VINTF_PRODUCT_COPY_FILES \
   BUILD_BROKEN_INCORRECT_PARTITION_IMAGES \
   BUILD_BROKEN_GENRULE_SANDBOXING \
+  BUILD_BROKEN_DONT_CHECK_SYSTEMSDK \
 
 _build_broken_var_list += \
   $(foreach m,$(AVAILABLE_BUILD_MODULE_TYPES) \
diff --git a/core/local_systemsdk.mk b/core/local_systemsdk.mk
index fcde700..3307e72 100644
--- a/core/local_systemsdk.mk
+++ b/core/local_systemsdk.mk
@@ -82,8 +82,10 @@
   endif
 
   ifneq ($(_system_sdk_version),$(filter $(_system_sdk_version),$(_supported_systemsdk_versions)))
-    $(call pretty-error,Incompatible LOCAL_SDK_VERSION '$(LOCAL_SDK_VERSION)'. \
-           System SDK version '$(_system_sdk_version)' is not supported. Supported versions are: $(_supported_systemsdk_versions))
+    ifneq (true,$(BUILD_BROKEN_DONT_CHECK_SYSTEMSDK)
+      $(call pretty-error,Incompatible LOCAL_SDK_VERSION '$(LOCAL_SDK_VERSION)'. \
+             System SDK version '$(_system_sdk_version)' is not supported. Supported versions are: $(_supported_systemsdk_versions))
+    endif
   endif
   _system_sdk_version :=
   _supported_systemsdk_versions :=
diff --git a/core/soong_config.mk b/core/soong_config.mk
index 193ac18..b6ce2a7 100644
--- a/core/soong_config.mk
+++ b/core/soong_config.mk
@@ -299,6 +299,7 @@
 $(call add_json_bool, BuildBrokenVendorPropertyNamespace,  $(filter true,$(BUILD_BROKEN_VENDOR_PROPERTY_NAMESPACE)))
 $(call add_json_bool, BuildBrokenIncorrectPartitionImages, $(filter true,$(BUILD_BROKEN_INCORRECT_PARTITION_IMAGES)))
 $(call add_json_list, BuildBrokenInputDirModules,          $(BUILD_BROKEN_INPUT_DIR_MODULES))
+$(call add_json_bool, BuildBrokenDontCheckSystemSdk,       $(filter true,$(BUILD_BROKEN_DONT_CHECK_SYSTEMSDK)))
 
 $(call add_json_list, BuildWarningBadOptionalUsesLibsAllowlist,    $(BUILD_WARNING_BAD_OPTIONAL_USES_LIBS_ALLOWLIST))