Fix mac build for nativebridge tests.

Bug: 17671501

(cherry picked from commit 2e5e8cc92081da6b0af658d12a60334acea441a1)

Change-Id: Id0d729a25a5cea2fed5005cdea750e9e94f46d21
diff --git a/libnativebridge/tests/PreInitializeNativeBridge_test.cpp b/libnativebridge/tests/PreInitializeNativeBridge_test.cpp
index 9b487d7..84078f7 100644
--- a/libnativebridge/tests/PreInitializeNativeBridge_test.cpp
+++ b/libnativebridge/tests/PreInitializeNativeBridge_test.cpp
@@ -31,8 +31,8 @@
 static constexpr const char* kTestData = "PreInitializeNativeBridge test.";
 
 TEST_F(NativeBridgeTest, PreInitializeNativeBridge) {
-#ifndef __APPLE_         // Mac OS does not support bind-mount.
-#ifndef HAVE_ANDROID_OS  // Cannot write into the hard-wired location.
+#ifndef __APPLE__         // Mac OS does not support bind-mount.
+#ifndef HAVE_ANDROID_OS   // Cannot write into the hard-wired location.
     // Try to create our mount namespace.
     if (unshare(CLONE_NEWNS) != -1) {
         // Create a dummy file.