Refactor libart_runtime_headers_ndk to a header lib also used by libart
itself.

This renames it and drops `sdk_version: "current"` as well.

Test: art/build/apex/runtests.sh
Test: m art-module-sdk art-module-{host,test}-exports
Bug: 204364566
Change-Id: I62c18fb1406e96865ad60d5022dcc4b60e778cbd
diff --git a/tools/cpp-define-generator/Android.bp b/tools/cpp-define-generator/Android.bp
index 3c6acb9..b27ccd6 100644
--- a/tools/cpp-define-generator/Android.bp
+++ b/tools/cpp-define-generator/Android.bp
@@ -35,7 +35,7 @@
     header_libs: [
         "art_libartbase_headers", // For base/bit_utils.h
         "jni_headers",
-        "libart_runtime_headers_ndk",
+        "libart_headers",
         "libdexfile_all_headers", // For dex/modifiers.h
     ],
     // Produce text file rather than binary.