Auto merge of #17726 - paulrouget:rm_WindowNavigateMsg, r=jdm

Remove WindowNavigateMsg

Two reasons:

- We want to be able to jump further in history from the embedder.
- We don't want to have an extra translation step in the compositor, where `WindowNavigateMsg` is translated to `TraversalDirection`

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

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components/compositing/compositor.rs

@@ -35,7 +35,7 @@ use time::{precise_time_ns, precise_time_s};
 use touch::{TouchHandler, TouchAction};
 use webrender;
 use webrender_api::{self, ClipId, LayoutPoint, LayoutVector2D, ScrollEventPhase, ScrollLocation, ScrollClamping};
-use windowing::{self, MouseWindowEvent, WindowEvent, WindowMethods, WindowNavigateMsg};
+use windowing::{self, MouseWindowEvent, WindowEvent, WindowMethods};
 
 #[derive(Debug, PartialEq)]
 enum UnableToComposite {
@@ -1294,11 +1294,7 @@ impl<Window: WindowMethods> IOCompositor<Window> {
         });
     }
 
-    fn on_navigation_window_event(&self, direction: WindowNavigateMsg) {
-        let direction = match direction {
-            windowing::WindowNavigateMsg::Forward => TraversalDirection::Forward(1),
-            windowing::WindowNavigateMsg::Back => TraversalDirection::Back(1),
-        };
+    fn on_navigation_window_event(&self, direction: TraversalDirection) {
         let top_level_browsing_context_id = match self.root_pipeline {
             Some(ref pipeline) => pipeline.top_level_browsing_context_id,
             None => return warn!("Sending navigation to constellation with no root pipeline."),

components/compositing/windowing.rs

@@ -8,7 +8,7 @@ use compositor_thread::EventLoopWaker;
 use euclid::{Point2D, Size2D};
 use euclid::{TypedPoint2D, TypedRect, ScaleFactor, TypedSize2D};
 use gleam::gl;
-use msg::constellation_msg::{Key, KeyModifiers, KeyState};
+use msg::constellation_msg::{Key, KeyModifiers, KeyState, TraversalDirection};
 use net_traits::net_error_list::NetError;
 use script_traits::{DevicePixel, LoadData, MouseButton, TouchEventType, TouchId, TouchpadPressurePhase};
 use servo_geometry::DeviceIndependentPixel;
@@ -25,12 +25,6 @@ pub enum MouseWindowEvent {
     MouseUp(MouseButton, TypedPoint2D<f32, DevicePixel>),
 }
 
-#[derive(Clone)]
-pub enum WindowNavigateMsg {
-    Forward,
-    Back,
-}
-
 /// Events that the windowing system sends to Servo.
 #[derive(Clone)]
 pub enum WindowEvent {
@@ -66,7 +60,7 @@ pub enum WindowEvent {
     /// Sent when the user resets zoom to default.
     ResetZoom,
     /// Sent when the user uses chrome navigation (i.e. backspace or shift-backspace).
-    Navigation(WindowNavigateMsg),
+    Navigation(TraversalDirection),
     /// Sent when the user quits the application
     Quit,
     /// Sent when a key input state changes