[bugfix] QueryGenerator may have action="query" parameter

The constructor of QueryGenerator may have action="query" as
arcument.

The current release always raise the Error message when an action
parameter is given, even the parameter's value is "query" because
"action" != "query" is always true.

This patch fixes the constructor in the right way.

Change-Id: I7b4f957b3aa344f8836e0a360f32b6af3a7dd589
Merge "[bugfix] QueryGenerator may have action="query" parameter"