Merge "Support `LOCAL_SDK_VERSION := current` for NDK."

  # missing API levels to existing ones where necessary, but we're not doing

  # missing API levels to existing ones where necessary, but we're not doing

  # that for the generated libraries. Clip the API level to the minimum where

  # that for the generated libraries. Clip the API level to the minimum where

  # appropriate.

  # appropriate.

  my_ndk_api := $(LOCAL_SDK_VERSION)

  ifneq ($(my_ndk_api),current)

      my_ndk_api := $(call math_max,$(LOCAL_SDK_VERSION),$(my_min_sdk_version))

      my_ndk_api := $(call math_max,$(LOCAL_SDK_VERSION),$(my_min_sdk_version))

  endif

  my_ndk_api_def := $(my_ndk_api)

  my_ndk_hist_api := $(my_ndk_api)

  ifeq ($(my_ndk_api),current)

    my_ndk_api_def := __ANDROID_API_FUTURE__

    # The last API level supported by the old prebuilt NDKs.

    my_ndk_hist_api := 24

  endif

  # Traditionally this has come from android/api-level.h, but with the libc

  # Traditionally this has come from android/api-level.h, but with the libc

  # headers unified it must be set by the build system since we don't have

  # headers unified it must be set by the build system since we don't have

  # per-API level copies of that header now.

  # per-API level copies of that header now.

  my_cflags += -D__ANDROID_API__=$(my_ndk_api)

  my_cflags += -D__ANDROID_API__=$(my_ndk_api_def)

  my_ndk_source_root := \

  my_ndk_source_root := \

      $(HISTORICAL_NDK_VERSIONS_ROOT)/$(LOCAL_NDK_VERSION)/sources

      $(HISTORICAL_NDK_VERSIONS_ROOT)/$(LOCAL_NDK_VERSION)/sources

  my_ndk_sysroot := \

  my_ndk_sysroot := \

    $(HISTORICAL_NDK_VERSIONS_ROOT)/$(LOCAL_NDK_VERSION)/platforms/android-$(my_ndk_api)/arch-$(my_arch)

    $(HISTORICAL_NDK_VERSIONS_ROOT)/$(LOCAL_NDK_VERSION)/platforms/android-$(my_ndk_hist_api)/arch-$(my_arch)

  my_built_ndk := $(SOONG_OUT_DIR)/ndk

  my_built_ndk := $(SOONG_OUT_DIR)/ndk

  my_ndk_triple := $($(LOCAL_2ND_ARCH_VAR_PREFIX)TARGET_NDK_TRIPLE)

  my_ndk_triple := $($(LOCAL_2ND_ARCH_VAR_PREFIX)TARGET_NDK_TRIPLE)

  my_ndk_sysroot_include := \

  my_ndk_sysroot_include := \