Description of problem:

There are 2 minor bugs that I discovered when extending testing for the REST Query API.

1. Using the "workItemId" parameter for task or process instance queries, results in an exception.
2. The use of task query parameters does not trigger a 400 response when used with the /rest/query/runtime/process operation, and instead triggers an exception.

The solutions/fixes to these problems are:

1. Removing support for the "workItemId" parameter. Adding support for this parameter is non-trivial, and I believe that the parameter is hardly used.
2. Modifying the code to return a HTTP 400 code when task query parameters are used when querying process instances (/rest/query/runtime/process).

Version-Release number of selected component (if applicable):

6.1.1

How reproducible:

Always

Steps to Reproduce:
[1/workItemId]
1. Do a query (task or proc inst) with the "workItemId" parameter

[2/task query params]
1. Do a proc instance query API REST request using a task query param ("taskId", "potentialOwner", etc.).

Actual results:

An exception is thrown.

Expected results:

[1/workItemId]
1. A HTTP 400 code is returned with the message "workItemId" is not supported

[2/task query params]
1. a HTTP 400 code is returned with the message that the given query is not supported.

Additional info:

This bug is meant for product 6.1/community 6.2.