jni_generator: Make all object-returning natives return ScopedJavaLocalRef.

components/cronet/android/cronet_library_loader.cc

Index: components/cronet/android/cronet_library_loader.cc
diff --git a/components/cronet/android/cronet_library_loader.cc b/components/cronet/android/cronet_library_loader.cc
index ddc5f1ba4c958d220f3677ae8befafd7d0b508b4..8e38125344a4bab324b404b7f01453385a001f8a 100644
--- a/components/cronet/android/cronet_library_loader.cc
+++ b/components/cronet/android/cronet_library_loader.cc
@@ -113,8 +113,8 @@ void CronetInitOnMainThread(JNIEnv* env, jclass jcaller) {
   g_network_change_notifier = net::NetworkChangeNotifier::Create();
 }
 
-jstring GetCronetVersion(JNIEnv* env, jclass jcaller) {
-  return base::android::ConvertUTF8ToJavaString(env, CRONET_VERSION).Release();
+ScopedJavaLocalRef<jstring> GetCronetVersion(JNIEnv* env, jclass jcaller) {
+  return base::android::ConvertUTF8ToJavaString(env, CRONET_VERSION);
 }
 
 }  // namespace cronet