Missing configuration for dryRun jobs causes NPE

@jcondit

A query job created with dryRun = true has no configuration field. The following is the response I get from Jobs: insert.

{
 "kind": "bigquery#job",
 "etag": "\"Bop49sEVg6UBKwr7tLdL8AavHaw/LRPbO11E3VlTAE5UxM2F_Mfu01M\"",
 "jobReference": {
  "projectId": "gcloud-devel"
 },
 "status": {
  "state": "DONE"
 },
 "statistics": {
  "creationTime": "1452067884640",
  "totalBytesProcessed": "26",
  "query": {
   "totalBytesProcessed": "26",
   "totalBytesBilled": "0",
   "cacheHit": false
  }
 }
}

While if I create the same job with dryRun = false the configuration is present instead:

{
 "kind": "bigquery#job",
 "etag": "\"Bop49sEVg6UBKwr7tLdL8AavHaw/OI0lGTx2GlKc0VoAAYS-fIXHWok\"",
 "id": "gcloud-devel:job_nixqXTMu-mS9U26Ixnxr9KZxCyc",
 "selfLink": "https://www.googleapis.com/bigquery/v2/projects/gcloud-devel/jobs/job_nixqXTMu-mS9U26Ixnxr9KZxCyc",
 "jobReference": {
  "projectId": "gcloud-devel",
  "jobId": "job_nixqXTMu-mS9U26Ixnxr9KZxCyc"
 },
 "configuration": {
  "query": {
   "query": "select StringField from gcloud_test_dataset_temp_6c127c49_9574_4e17_ad2b_8e85071997aa.testing_table",
   "destinationTable": {
    "projectId": "gcloud-devel",
    "datasetId": "_6bb2fc157573f6bd0fed98f3b039c1e71f26d7d1",
    "tableId": "anon5f489e91b602aaed3dc62a46d51ba3c070e5d03f"
   },
   "createDisposition": "CREATE_IF_NEEDED",
   "writeDisposition": "WRITE_TRUNCATE"
  },
  "dryRun": false
 },
 "status": {
  "state": "RUNNING"
 },
 "statistics": {
  "creationTime": "1452070358348",
  "startTime": "1452070358585"
 },
 "user_email": "..."
}

While this does not affect the functionality itself I was wondering whether configuration should be returned also for dry-run jobs for consistency? /cc @jcondit @jtigani

For what concerns gcloud-java the absence of a configuration causes a NPE to be thrown at JobInfo:297.