alt-tab - The app title in the top left of the top bar should change as the alt-tab focus changes

Ideally we should use _NET_WM_STATE_FOCUSED rather than _NET_ACTIVE_WINDOW for determining which window is logically active.

http://mail.gnome.org/archives/wm-spec-list/2011-October/msg00000.html

_NET_WM_STATE_FOCUSED allows window managers to specify which window(s) are logically in focus rather than _NET_ACTIVE_WINDOW which is restricted to which window has the input focus, which we can't just change whenever we want for various reasons. Compiz still needs support for this, I'm pretty sure I added it in last week but I haven't had a chance to test it yet.

This bug was fixed in the package unity - 5.2.0-0ubuntu1

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unity (5.2.0-0ubuntu1) precise; urgency=low

  * New upstream release.
    - Unity needs a way to switch (tab) between windows on current workspace
      (LP: #863399)
    - compiz crashed with SIGSEGV in BamfLauncherIcon::NameForWindow()
      (LP: #865840)
    - Gradual degradation in desktop performance. (LP: #888039)
    - compiz (unity) crashes with SIGSEGV when a window is minimized.
      (LP: #918329)
    - FavoriteStore external change support (LP: #681503)
    - Launcher - Make Launcher left of screen reveal more responsive and less
      prone to false positives (LP: #765819)
    - Window auto-maximise functionality should be disabled on monitors with a
      resolution above 1024 x 600 (LP: #797808)
    - Dash: very high latency responding to input (LP: #828582)
    - Dash - Behaviour of the 'All' button in the Dash filters broken in
      several ways (LP: #841864)
    - alt-tab - The app title in the top left of the top bar should change as
      the alt-tab focus changes (LP: #855516)
    - Keyboard shortcut - Add keyboard shortcut hint overlay that is displayed
      when a user presses and holds the Super key (LP: #855532)
    - Unity crashes when started in an environment without utouch support
      (LP: #860707)
    - Dash - Remove Dash Home shortcut icons (LP: #885738)
    - Dash - Most Frequently Used apps change to Recently Used, without
      Launcher favorites (LP: #893214)
    - Should have a launcher on every monitor (LP: #915944)
    - Launcher autohide behaviour on multi-monitor (LP: #915946)
    - the unity wrapper should kill compiz before restarting it (LP: #919132)
    - Launcher - Implement workspace/launcher cross interactions (LP: #690143)
    - Application icons should only display windows from the current workspace
      in the window spread (LP: #689733)
    - Notification area ("system tray") missing when using dual monitors of
      different sizes, with their bottoms aligned (LP: #778256)
    - Clicking Nautilus launcher icon fails to open a Nautilus file explorer
      window when copying a file and all other Nautilus windows are closed /
      bamf should skip the taskbar (LP: #784804)
    - Dash - the search box is not aligned correctly relative to the Launcher
      BFB button (LP: #838904)
    - Dash - A expand/collapse arrow is missing from all the filter category
      headers (LP: #841870)
    - Dash - the filter buttons should not have a mouse over state
      (LP: #838901)
    - Dash - the "Filter results" text is the wrong size, wrong font weight,
      and aligned incorrectly in both the vertical and horizontal axis
      (LP: #863240)
    - Add SUPER+TAB switching mode that enables the user to switch
      applications via the Launcher (LP: #891620)
    - Software Centre - automatically add app icon to launcher (LP: #761851)
    - Compiz add transparency to titlebar along with the panel (LP: #912682)
    - The search box is too opaque and dark (LP: #913717)
    - Dash - Make statefulness of Dash Home and Dash Lenses consistent
      (LP: #914759)
    - Unity 5.0: "All" button for filters render as "..." (LP: #91...