Concurrence issues accessing dashboard data

Description of problem:

Data displayed by dashboards is not protected against concurrence access. If two users on different machines start manipulating the same dashboard (submitting filter requests) then the data displayed by the indicators does not reflect the filters applied. It seems filtered data displayed by the two dashboards is shared and hence what one user does it affects what another user is seeing. Another major problem are errors raised by the tool at random times due to a lack of concurrence control in the processing of filter requests.

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

6.0.x

How reproducible:

Open two different browser sessions:

Steps to Reproduce:
1. Go to the same dashboard page. For example, the Expense reports dashboard.
2. Start submitting filter requests from the filter form on the left.
3. Requests must be submitted at the same time (two QE engs. might be necessary here)

Actual results:

Screenshot 1: inconsistent filter status on the dashboard.
Screenshot 2: error raised by the tool after a concurrent filter request.

Expected results:

Data displayed in a dashboard should be isolated from other dashboards.
Concurrence requests must be handled properly.