[orca] Treat switcher selection change events as script-activatable events

[Joanmarie Diggs <joanied src gnome org>]

commit 7c07bdc4e0af47f1c717d14934b876bf6f39f885
Author: Joanmarie Diggs <jdiggs igalia com>
Date:   Wed Mar 6 22:16:02 2019 +0100

    Treat switcher selection change events as script-activatable events

 src/orca/scripts/switcher/script.py | 8 ++++++++
 1 file changed, 8 insertions(+)
---
diff --git a/src/orca/scripts/switcher/script.py b/src/orca/scripts/switcher/script.py
index 22e7b8966..ca6986080 100644
--- a/src/orca/scripts/switcher/script.py
+++ b/src/orca/scripts/switcher/script.py
@@ -46,6 +46,14 @@ class Script(default.Script):
 
         return Utilities(self)
 
+    def isActivatableEvent(self, event):
+        """Returns True if this event should activate this script."""
+
+        if self.utilities.isSwitcherSelectionChangeEventType(event):
+            return True
+
+        return super().isActivatableEvent(event)
+
     def _handleSwitcherEvent(self, event):
         """Presents the currently selected item, if appropriate."""