Spurious navigation history entry added when clearing a search

This bug was fixed in the package software-center - 4.1.23.4

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software-center (4.1.23.4) oneiric; urgency=low

  [ Matthew McGowan ]
  * utils/submit_review_gtk3.py:
    - fix crash when submitting a review (LP: #852016)
  * fix the overlay icon position in the (lobby|subcat) featured tiles
  * fix the backforward button such that the border-radius is switched
    when in rtl mode.
  * softwarecenter/ui/gtk3/views/appdetailsview_gtk.py:
    - fix stray dotted lines at bottom of the "not found"
      screen (LP: #853514)
  * softwarecenter/ui/gtk3/widgets/buttons.py:
    - add a focus ring for the "More" buttons on the
      home screen (LP: #854177)
  * softwarecenter/ui/gtk3/widgets/exhibits.py:
    - add a focus ring for the exhibits banner (LP: #854168)
  * check the button-release occurs within the exhibit banner
    (LP: #848805)
  * add additional checks to ensure we bail on a NoneType within
    apptreeview._on_button_press_event. also switch some StateType's
    to the Gtk3 correct StateFlags'
  * reimplement the focal frames for focal CellRendererButtons
    in the apptreeview
  * lp:~mmcg069/software-center/rtl-improvements
    - make the appview progress bar fill in the correct direction when in rtl
      mode
    - also improve the positioning of the installed overlay icon in both ltr
      and rtl modes.
  * lp:~mmcg069/software-center/nav-improvements
    - correct the navhistory behaviour when a user clears the search_entry,
      remove spurious navhistory items, improve unit test (LP: #854047)
  * lp:~mmcg069/software-center/lobby-work
    - update the lobby and subcat views when selecting to view "Canonical
      Maintained Software", other lobby fixes and cleanup (LP: #835025)
  * lp:~mmcg069/software-center/description-improvements:
    - improvements to the description area in the details view, make
      description text selectable, update unit test (LP: #854368)
  * lp:~mmcg069/software-center/Bug846204:
    - a solution to LP: #846204

  [ Kiwinote ]
  * softwarecenter/db/application.py:
    - fix UnicodeDecodeError in __init__ (LP: #838791)
  * softwarecenter/db/debfile.py:
    - fix UnicodeDecodeError in __init__ (LP: #835887)
  * softwarecenter/ui/gtk3/widgets/buttons.py:
    - draw focus-line for category tiles and subcategory tiles
    - make featuredtiles accessible
  * softwarecenter/ui/gtk3/widgets/description.py:
    - fix crash in rendering bullet points in rtl layouts
  * softwarecenter/ui/gtk3/widgets/exhibits.py:
    - make exhibits accessible

  [ Gary Lasker ]
  * utils/submit_review_gtk3.py:
    - fix crash if an error occurs while submitting
      a review (LP: #854187)
  * softwarecenter/ui/gtk3/widgets/apptreeview.py:
    - check that a category is not selected before updating,
      fixes a crash on e.g. a network change event (LP: #848085)
  * softwarecenter/ui/gtk3/panes/installedpane.py:
    - display a spinner while loading the oneconf
      list view
  * pyflakes fixes

  [ Michael Vogt ]
  * softwarecenter/ui/gtk3/views/purchaseview.py,
    test/gtk3/test_purchase.py:
    - ensure to never log sensitive oauth token data to the console
      from webkit and add test
  * debian/c...