Android production build `MissingDefaultResource` lint error.

When building Android app for production build I get this lint error. Its because generator builds only folders `drawable-land-xxxx` and `drawable-port-xxx`. There should be build also default `drawable-xxxx` folders I think.

Temporary solution is suppress this lint error adding this code to `android/app/build.gradle`

```
application {
....
lintOptions{
disable 'MissingDefaultResource'
}
}
```
More info about lint error (source: http://tools.android.com/tips/lint-checks)

MissingDefaultResource
----------------------
Summary: Missing Default

Priority: 6 / 10
Severity: Fatal
Category: Correctness

If a resource is only defined in folders with qualifiers like -land or -en,
and there is no default declaration in the base folder (layout or values etc),
then the app will crash if that resource is accessed on a device where the
device is in a configuration missing the given qualifier.

As a special case, drawables do not have to be specified in the base folder;
if there is a match in a density folder (such as drawable-mdpi) that image
will be used and scaled. Note however that if you only specify a drawable in
a folder like drawable-en-hdpi, the app will crash in non-English locales.

There may be scenarios where you have a resource, such as a -fr drawable,
which is only referenced from some other resource with the same qualifiers
(such as a -fr style), which itself has safe fallbacks. However, this still
makes it possible for somebody to accidentally reference the drawable and
crash, so it is safer to create a default dummy fallback in the base folder.
Alternatively, you can suppress the issue by adding
tools:ignore="MissingDefaultResource" on the element.

(This scenario frequently happens with string translations, where you might
delete code and the corresponding resources, but forget to delete a
translation. There is a dedicated issue id for that scenario, with the id
ExtraTranslation.)

Start by tracing the generator code that creates the Android drawable-land-xxxx and drawable-port-xxx folders, then inspect android/app/build.gradle and reproduce the production lint failure. Done means the generator also produces safe default drawable-xxxx resources and the production build no longer reports MissingDefaultResource without suppressing the lint check.

Written by the indexing model from the issue text.