[Mac] Add system share menu

chrome/browser/ui/cocoa/share_menu_controller.h

Index: chrome/browser/ui/cocoa/share_menu_controller.h
diff --git a/chrome/browser/ui/cocoa/share_menu_controller.h b/chrome/browser/ui/cocoa/share_menu_controller.h
new file mode 100644
index 0000000000000000000000000000000000000000..2be8d9ac5fdfedfbea71146529e82c666bd41064
--- /dev/null
+++ b/chrome/browser/ui/cocoa/share_menu_controller.h
@@ -0,0 +1,23 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_UI_COCOA_SHARE_MENU_CONTROLLER_H_
+#define CHROME_BROWSER_UI_COCOA_SHARE_MENU_CONTROLLER_H_
+
+#import <Cocoa/Cocoa.h>
+
+// Set this as the delegate of a menu to populate with potential sharing service
+// items. Handles performing share actions chosen by the user and opening the
+// sharing service pref pane so that the user can enable or disable services.
+@interface ShareMenuController
+    : NSObject<NSMenuDelegate, NSSharingServiceDelegate>
+@end
+
+@interface ShareMenuController (ExposedForTesting)
+// Whether the menu should add a "More..." item that opens the
+// Sharing Extension pref pane.
++ (BOOL)shouldShowMoreItem;
+@end
+
+#endif  // CHROME_BROWSER_UI_COCOA_SHARE_MENU_CONTROLLER_H_