Add and use constants for the Android API levels.

Test: bionic tests still pass
Change-Id: If1b619cfc9db1d3f5d91f14f2ace71058dca0c4a
diff --git a/libc/include/android/api-level.h b/libc/include/android/api-level.h
index 6dd4c18..c83c18d 100644
--- a/libc/include/android/api-level.h
+++ b/libc/include/android/api-level.h
@@ -43,4 +43,17 @@
 #define __ANDROID_API__ __ANDROID_API_FUTURE__
 #endif
 
+#define __ANDROID_API_G__ 9
+#define __ANDROID_API_I__ 14
+#define __ANDROID_API_J__ 16
+#define __ANDROID_API_J_MR1__ 17
+#define __ANDROID_API_J_MR2__ 18
+#define __ANDROID_API_K__ 19
+#define __ANDROID_API_L__ 21
+#define __ANDROID_API_L_MR1__ 22
+#define __ANDROID_API_M__ 23
+#define __ANDROID_API_N__ 24
+#define __ANDROID_API_N_MR1__ 25
+#define __ANDROID_API_O__ 26
+
 #endif /* ANDROID_API_LEVEL_H */