Add a way to make Drawable clicks not change focus

[smoogipoo]

RFC. This is useful in situations like the osu!-side collection dropdown, which expects to remain open when the add/remove button is pressed.

Master:

2024-05-23.00-14-01.mp4

With this PR (+ diff below):

2024-05-23.00-14-45.mp4

diff --git a/osu.Game/Collections/CollectionDropdown.cs b/osu.Game/Collections/CollectionDropdown.cs
index 15dd644073..c04689b097 100644
--- a/osu.Game/Collections/CollectionDropdown.cs
+++ b/osu.Game/Collections/CollectionDropdown.cs
@@ -202,7 +202,7 @@ public CollectionDropdownDrawableMenuItem(MenuItem item)
             [BackgroundDependencyLoader]
             private void load()
             {
-                AddInternal(addOrRemoveButton = new IconButton
+                AddInternal(addOrRemoveButton = new NoFocusChangeIconButton
                 {
                     Anchor = Anchor.CentreRight,
                     Origin = Anchor.CentreRight,
@@ -271,6 +271,11 @@ private void addOrRemove()
             }

             protected override Drawable CreateContent() => (Content)base.CreateContent();
+
+            private partial class NoFocusChangeIconButton : IconButton
+            {
+                public override bool ChangeFocusOnClick => false;
+            }
         }
     }
 }

[peppy]

i guess this works