bigquery: tabledata.list tracking

[pongad]

This issue tracks things we need to migrate query to use tabledata.list instead of getQueryResults RPC. Work is in bq-perf branch.

• [x] ~Remove~ InternalApi QueryResponse type
• [x] ~Remove~ InternalApi BigQuery.getQueryResults
  • Use getJob().getQueryResults instead
• [x] Give QueryResults fewer fields (#2592)
  • To get details of a job, use Job
• [x] Should Job.getQueryResults wait for query to finish?
• [x] What should BigQuery.query do?
  • alias of create?
  • return completed job?
  • return iterator?
  • What option should it accept?
  • Accept option for iterating, use default option for waiting?
• [x] Consider unified types of Job.getQueryResults and BigQuery.listTableData
• [x] Make sure benchmark actually improves
• [x] Make sure we don't retrogress on small queries

[pongad]

@vam-google @tswast I'm just copying from notes of meeting we had a couple of weeks ago. Could you check that we're on the same page?

[tswast]

:+1:

Regarding "What should BigQuery.query do?" my preference is "alias of create". But the other options may be acceptable if any exceptions thrown while waiting for the job make it easy to get the full job resource so that the user can investigate errors further.

[pongad]

Everything done now. We're going to merge back to master.