Auto merge of #23988 - georgeroman:implement_pointer_up_and_down_actions, r=jdm

Implement pointerDown and pointerUp webdriver actions

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components/script_traits/lib.rs

@@ -798,6 +798,8 @@ pub enum WebDriverCommandMsg {
     SendKeys(BrowsingContextId, Vec<WebDriverInputEvent>),
     /// Act as if keys were pressed or release in the browsing context with the given ID.
     KeyboardAction(BrowsingContextId, KeyboardEvent),
+    /// Act as if the mouse was clicked in the browsing context with the given ID.
+    MouseButtonAction(MouseEventType, MouseButton, f32, f32),
     /// Set the window size.
     SetWindowSize(
         TopLevelBrowsingContextId,