JsonReader implementation erroneously reset `peeked` to PEEKED_NONE;
JsonTreeReader threw ArrayIndexOutOfBoundsException.

…object

For JsonReader this caused an IllegalStateException (in the past it caused
JsonReader to get stuck in an infinite loop); for JsonTreeReader it only
popped the empty iterator but not the JsonArray or JsonObject, which caused
peek() to again report END_ARRAY or END_OBJECT.

…ipped

This improves the JSON path when the value for a property was skipped and
before the subsequent property (or the end of the object) getPath() is called.