Can I get all the font styles in one text layer?
If I use different text style in one text layer, how can I get all the styles?

for example:
![image](https://user-images.githubusercontent.com/13414731/72418313-8b115a80-37b5-11ea-88cc-a4ec01ef1dab.png)

and the sketch js api returns:

![image](https://user-images.githubusercontent.com/13414731/72418367-a9775600-37b5-11ea-92af-25836425f3c3.png)

it seems to that I can get them from nativeObject

![image](https://user-images.githubusercontent.com/13414731/72418501-eba09780-37b5-11ea-870c-ca0603b24383.png)

and it is a simple way to get them?
