Do not keep selected documents when user changes content view

Steps to reproduce:

1. Save a search (for instance documents created by a specified user).
   -> Only documents corresponding to the search criteria are displayed.
2. Click on "Select all".
   -> All displayed documents are checked.
3. In the Search drop down list, selet Default search.
   -> The list of documents is refreshed, and all documents are displayed.
   -> Documents are not checked. But bottom documents are still available.
4. Click on "Add to worklist".
   -> Previously selected documents are added to the worklist.

=> When user changes search, the list of selected documents should be emptied.