Revert "Add OutputCommand::SetPointerPosition to set mouse position" (#5867)

Reverts emilk/egui#5776

I noticed that this is already a `ViewportCommand`. Sorry for not seeing
that earlier.

crates/egui/src/context.rs

@@ -1494,11 +1494,6 @@ impl Context {
         self.send_cmd(crate::OutputCommand::CopyImage(image));
     }
 
-    /// Set the mouse cursor position (if the platform supports it).
-    pub fn set_pointer_position(&self, position: Pos2) {
-        self.send_cmd(crate::OutputCommand::SetPointerPosition(position));
-    }
-
     /// Format the given shortcut in a human-readable way (e.g. `Ctrl+Shift+X`).
     ///
     /// Can be used to get the text for [`crate::Button::shortcut_text`].

crates/egui/src/data/output.rs

@@ -95,9 +95,6 @@ pub enum OutputCommand {
 
     /// Open this url in a browser.
     OpenUrl(OpenUrl),
-
-    /// Set the mouse cursor position (if the platform supports it).
-    SetPointerPosition(emath::Pos2),
 }
 
 /// The non-rendering part of what egui emits each frame.