Auto merge of #20707 - gterzian:embedder_handling_of_prompts_and_alerts_2, r=payl

Embedder handling of prompts and alerts

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Allow embedder to allow alerts and prompts, but via constellation forwarding messages from script.

---
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- [ ] `./mach build -d` does not report any errors
- [ ] `./mach build-geckolib` does not report any errors
- [ ] `./mach test-tidy` does not report any errors
- [ ] These changes fix #19992  (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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components/script/dom/window.rs

@@ -48,6 +48,7 @@ use dom::windowproxy::WindowProxy;
 use dom::worklet::Worklet;
 use dom::workletglobalscope::WorkletGlobalScopeType;
 use dom_struct::dom_struct;
+use embedder_traits::EmbedderMsg;
 use euclid::{Point2D, Vector2D, Rect, Size2D, TypedPoint2D, TypedScale, TypedSize2D};
 use fetch;
 use ipc_channel::ipc::IpcSender;
@@ -114,8 +115,6 @@ use task_source::performance_timeline::PerformanceTimelineTaskSource;
 use task_source::user_interaction::UserInteractionTaskSource;
 use time;
 use timers::{IsInterval, TimerCallback};
-#[cfg(any(target_os = "macos", target_os = "linux", target_os = "windows"))]
-use tinyfiledialogs::{self, MessageBoxIcon};
 use url::Position;
 use webdriver_handlers::jsval_to_webdriver;
 use webrender_api::{ExternalScrollId, DeviceIntPoint, DeviceUintSize, DocumentId};
@@ -444,18 +443,6 @@ impl Window {
     }
 }
 
-#[cfg(any(target_os = "macos", target_os = "linux", target_os = "windows"))]
-fn display_alert_dialog(message: &str) {
-    if !opts::get().headless {
-        tinyfiledialogs::message_box_ok("Alert!", message, MessageBoxIcon::Warning);
-    }
-}
-
-#[cfg(not(any(target_os = "macos", target_os = "linux", target_os = "windows")))]
-fn display_alert_dialog(_message: &str) {
-    // tinyfiledialogs not supported on Android
-}
-
 // https://html.spec.whatwg.org/multipage/#atob
 pub fn base64_btoa(input: DOMString) -> Fallible<DOMString> {
     // "The btoa() method must throw an InvalidCharacterError exception if
@@ -541,14 +528,10 @@ impl WindowMethods for Window {
             stdout.flush().unwrap();
             stderr.flush().unwrap();
         }
-
         let (sender, receiver) = ProfiledIpc::channel(self.global().time_profiler_chan().clone()).unwrap();
-        self.send_to_constellation(ScriptMsg::Alert(s.to_string(), sender));
-
-        let should_display_alert_dialog = receiver.recv().unwrap();
-        if should_display_alert_dialog {
-            display_alert_dialog(&s);
-        }
+        let msg = EmbedderMsg::Alert(s.to_string(), sender);
+        self.send_to_embedder(msg);
+        receiver.recv().unwrap();
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-window-closed
@@ -937,7 +920,7 @@ impl WindowMethods for Window {
         //TODO determine if this operation is allowed
         let dpr = self.device_pixel_ratio();
         let size = TypedSize2D::new(width, height).to_f32() * dpr;
-        self.send_to_constellation(ScriptMsg::ResizeTo(size.to_u32()));
+        self.send_to_embedder(EmbedderMsg::ResizeTo(size.to_u32()));
     }
 
     // https://drafts.csswg.org/cssom-view/#dom-window-resizeby
@@ -953,7 +936,8 @@ impl WindowMethods for Window {
         //TODO determine if this operation is allowed
         let dpr = self.device_pixel_ratio();
         let point = TypedPoint2D::new(x, y).to_f32() * dpr;
-        self.send_to_constellation(ScriptMsg::MoveTo(point.to_i32()));
+        let msg = EmbedderMsg::MoveTo(point.to_i32());
+        self.send_to_embedder(msg);
     }
 
     // https://drafts.csswg.org/cssom-view/#dom-window-moveby
@@ -1742,7 +1726,11 @@ impl Window {
         self.navigation_start_precise.set(time::precise_time_ns());
     }
 
-    fn send_to_constellation(&self, msg: ScriptMsg) {
+    pub fn send_to_embedder(&self, msg: EmbedderMsg) {
+        self.send_to_constellation(ScriptMsg::ForwardToEmbedder(msg));
+    }
+
+    pub fn send_to_constellation(&self, msg: ScriptMsg) {
         self.upcast::<GlobalScope>()
             .script_to_constellation_chan()
             .send(msg)