[orca] Flush live region messages when interrupting presentation

[Joanmarie Diggs <joanied src gnome org>]

commit b4ee1563fbeba594461dcbc9a577bf7728c8d858
Author: Joanmarie Diggs <jdiggs igalia com>
Date:   Mon Mar 9 14:32:36 2020 -0400

    Flush live region messages when interrupting presentation
    
    Otherwise users can get flooded by very chatty web apps.

 src/orca/scripts/web/script.py | 6 ++++++
 1 file changed, 6 insertions(+)
---
diff --git a/src/orca/scripts/web/script.py b/src/orca/scripts/web/script.py
index 9cba08984..80a7720f7 100644
--- a/src/orca/scripts/web/script.py
+++ b/src/orca/scripts/web/script.py
@@ -509,6 +509,12 @@ class Script(default.Script):
 
         return super().skipObjectEvent(event)
 
+    def presentationInterrupt(self):
+        super().presentationInterrupt()
+        msg = "WEB: Flushing live region messages"
+        debug.println(debug.LEVEL_INFO, msg, True)
+        self.liveRegionManager.flushMessages()
+
     def consumesKeyboardEvent(self, keyboardEvent):
         """Returns True if the script will consume this keyboard event."""