Merge "__ANDROID_UNGUARDED_AVAILABILITY__ is gone now."

cc/config/clang.go

@@ -151,8 +151,6 @@ func init() {
 		// This macro allows the bionic versioning.h to indirectly determine whether the
 		// option -Wunguarded-availability is on or not.
 		"-D__ANDROID_UNAVAILABLE_SYMBOLS_ARE_WEAK__",
-		// TODO: remove this once prebuilt SDKs are only using the above macro instead.
-		"-D__ANDROID_UNGUARDED_AVAILABILITY__",
 	}, " "))
 
 	pctx.StaticVariable("ClangExtraCppflags", strings.Join([]string{