StringIndexOutOfBoundsException opening themes

[nbradbury]

Can't repro this one. Happened on Nexus 5 KitKat.

java.lang.StringIndexOutOfBoundsException: length=0; regionStart=0; regionLength=-1
            at java.lang.String.startEndAndLength(String.java:588)
            at java.lang.String.substring(String.java:1475)
            at org.wordpress.android.models.Theme.fromJSON(Theme.java:190)
            at org.wordpress.android.ui.themes.ThemeBrowserActivity$5.onResponse(ThemeBrowserActivity.java:237)
            at org.wordpress.android.ui.themes.ThemeBrowserActivity$5.onResponse(ThemeBrowserActivity.java:232)
            at com.wordpress.rest.RestRequest.deliverResponse(RestRequest.java:60)
            at com.wordpress.rest.RestRequest.deliverResponse(RestRequest.java:17)
            at com.android.volley.ExecutorDelivery$ResponseDeliveryRunnable.run(ExecutorDelivery.java:99)

Problem occurs in models/Theme.java here: