message: fixed PHP_API crash when get not exists key.
diff: @@ -413,11 +413,19 @@ public:
  Variant operator [](int i)
  {
  zval *ret = zend_hash_index_find(Z_ARRVAL_P(ptr()), (zend_ulong) i);
  + if (ret == NULL)
  + {
  + return Variant(nullptr);
  + }
  return Variant(ret);
  }
  Variant operator [](const char *key)
  {
  zval *ret = zend_hash_str_find(Z_ARRVAL_P(ptr()), key, strlen(key));
  + if (ret == NULL)
  + {
  + return Variant(nullptr);
  + }
  return Variant(ret);
  }
  bool remove(const char *key)
  