suppress unguarded-availability warning for only AServiceManager_waitForService

Test: build & presubmit
Change-Id: I4542f3809cb49470290b9b7e3f940a8644c301c7
diff --git a/service/Android.bp b/service/Android.bp
index 38c0110..7ddf068 100644
--- a/service/Android.bp
+++ b/service/Android.bp
@@ -107,10 +107,6 @@
         "-Werror",
         "-Wno-unused-parameter",
         "-Wthread-safety",
-
-        // AServiceManager_waitForService is available on only 31+, but it's still safe for Thread
-        // service because it's enabled on only 34+
-        "-Wno-unguarded-availability",
     ],
     srcs: [
         ":services.connectivity-netstats-jni-sources",
diff --git a/service/jni/com_android_server_ServiceManagerWrapper.cpp b/service/jni/com_android_server_ServiceManagerWrapper.cpp
index 0cd58f4..0e32726 100644
--- a/service/jni/com_android_server_ServiceManagerWrapper.cpp
+++ b/service/jni/com_android_server_ServiceManagerWrapper.cpp
@@ -25,7 +25,13 @@
 static jobject com_android_server_ServiceManagerWrapper_waitForService(
         JNIEnv* env, jobject clazz, jstring serviceName) {
     ScopedUtfChars name(env, serviceName);
+
+// AServiceManager_waitForService is available on only 31+, but it's still safe for Thread
+// service because it's enabled on only 34+
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wunguarded-availability"
     return AIBinder_toJavaBinder(env, AServiceManager_waitForService(name.c_str()));
+#pragma clang diagnostic pop
 }
 
 /*