Implement DbusMenu

Implements (most of) menus for use in DBus status icons.  Still left is
adding a default "click-action" item to the menu and showing a native
menu when the server does not support menus.

BUG=419673
R=thestig

Change-Id: Idc340581b9960ed9769b98857820eb8ab4a1c87f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1654489
Commit-Queue: Thomas Anderson <[email protected]>
Reviewed-by: Scott Violet <[email protected]>
Cr-Commit-Position: refs/heads/master@{#670346}
diff --git a/ui/views/linux_ui/status_icon_linux.h b/ui/views/linux_ui/status_icon_linux.h
index a9c65be1..652e436f 100644
--- a/ui/views/linux_ui/status_icon_linux.h
+++ b/ui/views/linux_ui/status_icon_linux.h
@@ -31,7 +31,7 @@
 
     virtual const gfx::ImageSkia& GetImage() const = 0;
     virtual const base::string16& GetToolTip() const = 0;
-    virtual const ui::MenuModel* GetMenuModel() const = 0;
+    virtual ui::MenuModel* GetMenuModel() const = 0;
 
     // This should be called at most once by the implementation.
     virtual void OnImplInitialized(bool success) = 0;