Make the native bridge API a C API.

In order to move the library into the runtime APEX.

Test: m and boot
Bug: 119840313
Bug: 122710865
Change-Id: I4aac5954d2fb5f9e3ba92e486d69f1e76614df92
diff --git a/libnativebridge/Android.bp b/libnativebridge/Android.bp
index 92fd2a2..59cd033 100644
--- a/libnativebridge/Android.bp
+++ b/libnativebridge/Android.bp
@@ -17,6 +17,11 @@
         "liblog",
     ],
 
+    stubs: {
+        symbol_file: "libnativebridge.map.txt",
+        versions: ["1"],
+    },
+
     export_include_dirs: ["include"],
 
     cflags: [