Ensure that BoxPrimitive only sees clean data...

...rather than forcing it to zero irrelevant bits itself.

Change-Id: Ibbd28db08b68fac84704a911a6f927f7d9343055
diff --git a/src/jni_internal.cc b/src/jni_internal.cc
index 5230de9..37ca93d 100644
--- a/src/jni_internal.cc
+++ b/src/jni_internal.cc
@@ -257,7 +257,7 @@
 
 static JValue InvokeWithArgArray(JNIEnv* public_env, Object* receiver, Method* method, JValue* args) {
   JNIEnvExt* env = reinterpret_cast<JNIEnvExt*>(public_env);
-  JValue result;
+  JValue result = { 0 };
   method->Invoke(env->self, receiver, args, &result);
   return result;
 }