JNI and class references

[mgd at swarm dot org (Marcus G. Daniels)]

In jni.cc, I see there's a template for jobject wrap_value, but not
one for jclass.  My experience with JNI is that a jclass returned
from a call like GetObjectClass is also a local reference.

Is it not appropriate to also have a wrap_value for jclass returns?
Specifically, like this:

template<>
static jclass
wrap_value (JNIEnv *env, jclass value)
{
  return value == NULL ? value : (jclass) _Jv_JNI_NewLocalRef (env, (jobject) value);
}

(The motivation being that code that expects that jclasses will be local
refs will be calling DeleteLocalRef in some circumstances, which will
crash the runtime if there isn't one.)