They were disabled during the Chromium 61 upgrade. Fix them and enable.

/cc @alespergl 
atom/common/api/atom_api_native_image.cc
v8::Isolate* isolate,
    const mate::Handle<atom::api::NativeImage>& val) {
  return val.ToV8();
}
bool Converter<mate::Handle<atom::api::NativeImage>>::FromV8(
    v8::Isolate* isolate, v8::Local<v8::Value> val,
    mate::Handle<atom::api::NativeImage>* out) {
  /
  base::FilePath path;
  if (ConvertFromV8(isolate, val, &path)) {
    *out = atom::api::NativeImage::CreateFromPath(isolate, path);
    /
    return !(*out)->image().IsEmpty();
  }
  WrappableBase* wrapper = static_cast<WrappableBase*>(internal::FromV8Impl(
      isolate, val));
  if (!wrapper)
    return false;
  *out = CreateHandle(isolate, static_cast<atom::api::NativeImage*>(wrapper));
  return true;
}
}  /
namespace {
void Initialize(v8::Local<v8::Object> exports, v8::Local<v8::Value> unused,