IMPALA-540: Impala debug webpage should report intermediate runtime profile

The JIRA description is not completely accurate - in fact a runtime profile
is produced for running queries, but updated fragment information was missing.

Change-Id: Icdc79fbc9675d01f23e242e1163a639d52e2df2a
Reviewed-on: http://gerrit.ent.cloudera.com:8080/1323
Reviewed-by: Nong Li <nong@cloudera.com>
Tested-by: jenkins