rename from testing/marionette/client/marionette_driver/selection.py
rename to layout/base/tests/marionette/selection.py

--- a/layout/base/tests/marionette/test_accessiblecaret_cursor_mode.py
+++ b/layout/base/tests/marionette/test_accessiblecaret_cursor_mode.py
@@ -1,18 +1,25 @@
 # -*- coding: utf-8 -*-
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 import string
+import sys
+import os
 
+# Add this directory to the import path.
+sys.path.append(os.path.dirname(__file__))
+
+from selection import (
+    SelectionManager,
+)
 from marionette_driver.by import By
 from marionette_driver.legacy_actions import Actions
-from marionette_driver.selection import SelectionManager
 from marionette_harness.marionette_test import (
     MarionetteTestCase,
     parameterized,
 )
 
 
 class AccessibleCaretCursorModeTestCase(MarionetteTestCase):
     '''Test cases for AccessibleCaret under cursor mode.

--- a/layout/base/tests/marionette/test_accessiblecaret_selection_mode.py
+++ b/layout/base/tests/marionette/test_accessiblecaret_selection_mode.py
@@ -1,18 +1,25 @@
 # -*- coding: utf-8 -*-
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 import re
+import sys
+import os
 
+# Add this directory to the import path.
+sys.path.append(os.path.dirname(__file__))
+
+from selection import (
+    SelectionManager,
+)
 from marionette_driver.by import By
 from marionette_driver.legacy_actions import Actions
-from marionette_driver.selection import SelectionManager
 from marionette_harness.marionette_test import (
     MarionetteTestCase,
     SkipTest,
     parameterized
 )
 
 
 def skip_if_not_rotatable(target):

--- a/testing/marionette/client/marionette_driver/__init__.py
+++ b/testing/marionette/client/marionette_driver/__init__.py
@@ -13,15 +13,14 @@ from marionette_driver import (
     decorators,
     errors,
     expected,
     geckoinstance,
     gestures,
     keys,
     localization,
     marionette,
-    selection,
     wait,
 )
 from marionette_driver.by import By
 from marionette_driver.date_time_value import DateTimeValue
 from marionette_driver.gestures import smooth_scroll, pinch
 from marionette_driver.wait import Wait