Correctly activate free camera on esc key hit.

PiperOrigin-RevId: 499576860
Change-Id: Ie1544d6efbed34384c6fbfe6784739c93f573095

Author: kevinzakka

dm_control/viewer/viewer.py

@@ -219,7 +219,7 @@ def initialize(self, physics, renderer_instance, touchpad):
     self._input_map.bind(self._free_camera.set_rotate_mode, _ROTATE_CAMERA)
     self._input_map.bind(self._free_camera.center, _CENTER_CAMERA)
     self._input_map.bind(self._free_camera.track, _TRACK_OBJECT)
-    self._input_map.bind(self._free_camera.free_look, _FREE_LOOK)
+    self._input_map.bind(self._camera_select.escape, _FREE_LOOK)
     self._input_map.bind(self._manipulator.select, _SELECT_OBJECT)
     self._input_map.bind_plane(self._manipulator.on_move)
 
@@ -312,6 +312,11 @@ def select_next(self):
       self._camera_idx = -1
     self._commit_selection()
 
+  def escape(self) -> None:
+    """Unconditionally switches to the free camera."""
+    self._camera_idx = -1
+    self._commit_selection()
+
   def _commit_selection(self):
     """Selects a controller that should go with the selected camera."""
     if self._camera_idx < 0: