Syntax highlighting broken for objects and classes in Reason

Using `dark-plus-syntax` (variation on the default theme) in VS Code 1.40.0:

Objects and classes have almost no syntax highlighting:

Note that in classes, but not objects, syntax highlighting breaks completely until the first semicolon (I put a method with a switch at the top of the class to demonstrate).

It seems that once you get inside a method (aside from the above mentioned case), things go back to relatively normal.

Reproduce the report in VS Code 1.40.0 using the dark-plus-syntax theme and a Reason file containing objects, classes, methods, and a switch before the first semicolon. Trace the syntax-highlighting behavior for these constructs; done means objects and classes retain appropriate highlighting, including class content before the first semicolon.

Written by the indexing model from the issue text.