Observed behavior: Attempt to include the field 'a.b' from document

triggers a verify assertion.
Expected behavior: The query projection implementation omits the array value in this case and does not assert.

c = db.c;
c.drop();

c.save( { a:[ 1 ] } );

printjson( c.aggregate( { $project:{ 'a.b':1 } } ) );
printjson( c.find( {}, { 'a.b':1 } ).toArray() );