Reset block association level inside array

[timcraft]

So I found some code like this:

it 'foo' do
  expect(x).to eq(
    [
      [ 1, 2 ],
    ]
  )
end

it 'bar' do
end

Current that raises syntax error, unexpected 'do' (expected: 'end-of-line') because there's no call to m_call_depth.pop() when parsing the array with a trailing comma as there is in the later return.

I've reduced that example as far as I can for the tests, but it needs to have enough structure for the call depth to matter and trigger the bug. I've also added a similar test case and fix for the return statement above the while loop.