Fixes broken tile resize introduced by #5044 (#5064)

### What

- Fixes #5061

### Checklist
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- [PR Build Summary](https://build.rerun.io/pr/5064)
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crates/re_viewport/src/viewport.rs

@@ -797,7 +797,6 @@ impl<'a, 'b> egui_tiles::Behavior<SpaceViewId> for TabViewer<'a, 'b> {
 
     fn on_edit(&mut self, edit_action: egui_tiles::EditAction) {
         match edit_action {
-            EditAction::TileResized | EditAction::TileDragged => {}
             EditAction::TileDropped => {
                 // TODO(ab): when we finally stop using egui_tiles as application-level data
                 //                  structure, this work-around should be unnecessary.
@@ -832,9 +831,13 @@ impl<'a, 'b> egui_tiles::Behavior<SpaceViewId> for TabViewer<'a, 'b> {
 
                 self.edited = true;
             }
-            EditAction::TabSelected => {
+            EditAction::TabSelected | EditAction::TileResized => {
                 self.edited = true;
             }
+            EditAction::TileDragged => {
+                // No synchronization needed, because TileDragged happens when a drag starts, so no tiles are actually
+                // modified. When the drag completes, then we get `TileDropped` and run the synchronization.
+            }
         }
     }
 }