-AinvariantArrays and two-dimensional arrays

If I try to typecheck the following code using the -AinvariantArrays 
command-line option:

  public static void main(String[] args) {
    assert any_null(new Object[][] { null }) == true;
  }

  public static boolean any_null(Object[] a) {
    return true;
  }

then I get the following error:

TwoDimensionalArray.java:7: error: [argument.type.incompatible] incompatible 
types in argument.
    assert any_null(new Object[][] { null }) == true;
                    ^
  found   : Object [] []
  required: Object []
1 error

A complete test case appears as 
checker-framework/checker/tests/nullness-invariantarrays/TwoDimensionalArray.jav
a (currently disabled).

Original issue reported on code.google.com by michael.ernst@gmail.com on 2 Jul 2015 at 5:46

Start by reproducing the report with the -AinvariantArrays option and inspect checker-framework/checker/tests/nullness-invariantarrays/TwoDimensionalArray.java, which is currently disabled. Determine why the two-dimensional array argument is rejected, then make the test pass without the incompatible-types error and re-enable it if appropriate.