chromeos: fix bug where "aw snap" page replaces first tab if it was a NTP when closing window with > 1 tab.

BUG=chromium-os:12088
TEST=verify bug per bug report.
Review URL: http://codereview.chromium.org/6882058

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@83031 0039d316-1c4b-4281-b951-d872f2087c98
    State(TabContentsWrapper* a_dst_contents,
          int a_dst_index,
          TabStripModelObserverAction a_action)
        : src_contents(NULL),
          dst_contents(a_dst_contents),
          src_index(-1),
          dst_index(a_dst_index),
          user_gesture(false),
          foreground(false),
          action(a_action) {
    }

    State(TabContentsWrapper* a_dst_contents,
          int a_dst_index,
          TabStripModelObserverAction a_action)
        : src_contents(NULL),
          dst_contents(a_dst_contents),
          src_index(-1),
          dst_index(a_dst_index),
          user_gesture(false),
          foreground(false),
          action(a_action) {
    }
