Extend notifications.mojom for expandable notifications.

components/arc/common/notifications.mojom

Index: components/arc/common/notifications.mojom
diff --git a/components/arc/common/notifications.mojom b/components/arc/common/notifications.mojom
index f1864a02abbefd344ebc1838faf16ad9cd404b7e..563ee775d83fa3bf24bfa168a1ba78ec22aa6112 100644
--- a/components/arc/common/notifications.mojom
+++ b/components/arc/common/notifications.mojom
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
-// Next MinVersion: 10
+// Next MinVersion: 11
 
 module arc.mojom;
 
@@ -20,6 +20,8 @@ enum ArcNotificationEvent {
   BUTTON_3_CLICKED = 4,
   BUTTON_4_CLICKED = 5,
   BUTTON_5_CLICKED = 6,
+  // expand/collapse the bundled notification
+  [MinVersion=10] TOGGLE_EXPANSION = 7,
 };
 
 // These values must be matched with the NOTIFICATION_TYPE_* constants in
@@ -36,6 +38,13 @@ struct ArcNotificationButton {
   string label;
 };
 
+[Extensible, MinVersion=10]
+enum ArcNotificationExpandState {
+  FIXED_SIZE = 0,
+  COLLAPSED = 1,
+  EXPANDED = 2,
+};
+
 struct ArcNotificationData {
   // Identifier of notification
   string key;
@@ -86,6 +95,9 @@ struct ArcNotificationData {
   // Accessibility text
   [MinVersion=8]
   string? accessible_name;
+  // Flag if the notification is expandable
+  [MinVersion=10]
+  ArcNotificationExpandState expand_state;
 };
 
 [MinVersion=2]