OnDemand Follow-on: Check that TabletHostingGoal set when Tablet splits

[dlmarion]

I as seeing in a recent test that the TabletHostingGoal was not being set when a Tablet split. Need to confirm this.

[keith-turner]

I noticed BulkSplitOptimizationIT was failing when I was running the bulk ITs for #3350. I wonder if this is why. Fixing this could wait unti lthe split code is moved out of the tserver. I am planning to start working on moving the split code soon, I have already experimented with this a few weeks ago.

[keith-turner]

I think the changes related to #3382 have fixed this, however we probably want explicit tests that verify the hosting goal after a split is correct in the new child tablets.

[jmark99]

@keith-turner , @dlmarion #3451 added tests that verify goals are set after a split occurs (testGetHostingGoals_DelayedSplits). If this test is sufficient for this ticket, then it can be closed.

[keith-turner]

@jmark99 those test look good to me. I think the test covers the case of splitting a table where all of the goals are the same. Could add a test to cover the case of splits in a table with mixed goals. Something like the following.

1. create table
2. add split m
3. set goal ALWAYS on last tablet
4. add splits d and s
5. verify two tablets have ONDEMAND and two have ALWAYS goal

Or modify an existing test for this case. I don't think this has to be done before closing this issue, I think the coverage is good in the test you already added. The above was just something I thought of when looking at the test.

[jmark99]

PR #3532 adds the additional test alluded to in this ticket.