[pitivi] layer: Remove unused TwoStateButton class

[Alexandru Băluț <alexbalut src gnome org>]

commit ad8b2c61e5bbcd0fcf8df2075023c8d325fcbe51
Author: Alexandru Băluț <alexandru balut gmail com>
Date:   Tue Aug 30 14:44:58 2016 +0200

    layer: Remove unused TwoStateButton class
    
    We could use Gtk.ToggleButton instead if needed.
    
    Differential Revision: https://phabricator.freedesktop.org/D1291

 pitivi/timeline/layer.py |   28 ----------------------------
 1 files changed, 0 insertions(+), 28 deletions(-)
---
diff --git a/pitivi/timeline/layer.py b/pitivi/timeline/layer.py
index 3595eb6..7738c65 100644
--- a/pitivi/timeline/layer.py
+++ b/pitivi/timeline/layer.py
@@ -22,7 +22,6 @@ from gettext import gettext as _
 from gi.repository import Gdk
 from gi.repository import GES
 from gi.repository import Gio
-from gi.repository import GObject
 from gi.repository import Gtk
 
 from pitivi.timeline import elements
@@ -32,33 +31,6 @@ from pitivi.utils.loggable import Loggable
 from pitivi.utils.timeline import Zoomable
 
 
-class TwoStateButton(Gtk.Button):
-    """Button with two states and according labels/images."""
-
-    __gsignals__ = {
-        "changed-state": (GObject.SignalFlags.RUN_LAST, None, (GObject.TYPE_PYOBJECT,),)
-    }
-
-    def __init__(self, state1="", state2=""):
-        Gtk.Button.__init__(self)
-        self.set_relief(Gtk.ReliefStyle.NONE)
-        self.connect("clicked", self._clickedCb)
-
-        self.set_states(state1, state2)
-        self._state = True
-
-        self.set_label(self.states[self._state])
-
-    def set_states(self, state1, state2):
-        self.states = {True: state1, False: state2}
-
-    def _clickedCb(self, unused_widget):
-        self._state = not self._state
-
-        self.set_label(self.states[self._state])
-        self.emit("changed-state", self._state)
-
-
 class SpacedSeparator(Gtk.EventBox):
     """A Separator with vertical spacing.