Code review comment for lp:~j-percival/fluidity/periodic-adaptivity-at-first-timestep

Hey James, thanks for committing this.

Two questions:
- what exactly do you mean by: "it may need extending for more insidious failure modes"
- is the new "periodic_adaptivity_at_first_timestep" test indeed simply a copy of the existing 'periodic_adaptivity' test with 'adapt_at_first_timestep' switched on? In this case, I'd much prefer to only have a single test (i.e. only switch on adapt_at_first_timestep in the exisitng 'periodic_adaptivity' test), as 'periodic_adaptivity_at_first_timestep' would duplicate the test coverage of 'periodic_adaptivity'.

The changes in the code look correct to me.