Auto merge of #15794 - paulrouget:head_parsed_url, r=asajeffrey

Notify embedder when history changes

`WindowMethods::set_page_url` is only called when the embedder set the URL. It is not called when the page url is updated. I believe that instead we should just pass the URL to `head_parsed`.

---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #15439 #15643 and #15642 (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [x] These changes do not require tests because I'm not sure how to test that

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components/compositing/compositor.rs

@@ -481,10 +481,6 @@ impl<Window: WindowMethods> IOCompositor<Window> {
                 self.change_page_title(pipeline_id, title);
             }
 
-            (Msg::ChangePageUrl(pipeline_id, url), ShutdownState::NotShuttingDown) => {
-                self.change_page_url(pipeline_id, url);
-            }
-
             (Msg::SetFrameTree(frame_tree, response_chan),
              ShutdownState::NotShuttingDown) => {
                 self.set_frame_tree(&frame_tree, response_chan);
@@ -519,11 +515,11 @@ impl<Window: WindowMethods> IOCompositor<Window> {
                 self.window.status(message);
             }
 
-            (Msg::LoadStart(back, forward), ShutdownState::NotShuttingDown) => {
-                self.window.load_start(back, forward);
+            (Msg::LoadStart, ShutdownState::NotShuttingDown) => {
+                self.window.load_start();
             }
 
-            (Msg::LoadComplete(back, forward, root), ShutdownState::NotShuttingDown) => {
+            (Msg::LoadComplete, ShutdownState::NotShuttingDown) => {
                 self.got_load_complete_message = true;
 
                 // If we're painting in headless mode, schedule a recomposite.
@@ -534,7 +530,7 @@ impl<Window: WindowMethods> IOCompositor<Window> {
                 // Inform the embedder that the load has finished.
                 //
                 // TODO(pcwalton): Specify which frame's load completed.
-                self.window.load_end(back, forward, root);
+                self.window.load_end();
             }
 
             (Msg::AllowNavigation(url, response_chan), ShutdownState::NotShuttingDown) => {
@@ -612,6 +608,10 @@ impl<Window: WindowMethods> IOCompositor<Window> {
                 self.window.head_parsed();
             }
 
+            (Msg::HistoryChanged(entries, current), ShutdownState::NotShuttingDown) => {
+                self.window.history_changed(entries, current);
+            }
+
             (Msg::PipelineVisibilityChanged(pipeline_id, visible), ShutdownState::NotShuttingDown) => {
                 self.pipeline_details(pipeline_id).visible = visible;
                 if visible {
@@ -707,10 +707,6 @@ impl<Window: WindowMethods> IOCompositor<Window> {
         }
     }
 
-    fn change_page_url(&mut self, _: PipelineId, url: ServoUrl) {
-        self.window.set_page_url(url);
-    }
-
     fn set_frame_tree(&mut self,
                       frame_tree: &SendableFrameTree,
                       response_chan: IpcSender<()>) {
@@ -906,7 +902,6 @@ impl<Window: WindowMethods> IOCompositor<Window> {
         self.got_load_complete_message = false;
         match ServoUrl::parse(&url_string) {
             Ok(url) => {
-                self.window.set_page_url(url.clone());
                 let msg = match self.root_pipeline {
                     Some(ref pipeline) => ConstellationMsg::LoadUrl(pipeline.id, LoadData::new(url, None, None)),
                     None => ConstellationMsg::InitLoadUrl(url)

components/compositing/compositor_thread.rs

@@ -13,7 +13,7 @@ use msg::constellation_msg::{Key, KeyModifiers, KeyState, PipelineId};
 use net_traits::image::base::Image;
 use profile_traits::mem;
 use profile_traits::time;
-use script_traits::{AnimationState, ConstellationMsg, EventResult};
+use script_traits::{AnimationState, ConstellationMsg, EventResult, LoadData};
 use servo_url::ServoUrl;
 use std::fmt::{Debug, Error, Formatter};
 use std::sync::mpsc::{Receiver, Sender};
@@ -75,16 +75,16 @@ pub enum Msg {
     ScrollFragmentPoint(webrender_traits::ClipId, Point2D<f32>, bool),
     /// Alerts the compositor that the current page has changed its title.
     ChangePageTitle(PipelineId, Option<String>),
-    /// Alerts the compositor that the current page has changed its URL.
-    ChangePageUrl(PipelineId, ServoUrl),
     /// Alerts the compositor that the given pipeline has changed whether it is running animations.
     ChangeRunningAnimationsState(PipelineId, AnimationState),
     /// Replaces the current frame tree, typically called during main frame navigation.
     SetFrameTree(SendableFrameTree, IpcSender<()>),
-    /// The load of a page has begun: (can go back, can go forward).
-    LoadStart(bool, bool),
-    /// The load of a page has completed: (can go back, can go forward, is root frame).
-    LoadComplete(bool, bool, bool),
+    /// The load of a page has begun
+    LoadStart,
+    /// The load of a page has completed
+    LoadComplete,
+    /// The history state has changed.
+    HistoryChanged(Vec<LoadData>, usize),
     /// Wether or not to follow a link
     AllowNavigation(ServoUrl, IpcSender<bool>),
     /// We hit the delayed composition timeout. (See `delayed_composition.rs`.)
@@ -142,11 +142,11 @@ impl Debug for Msg {
             Msg::ScrollFragmentPoint(..) => write!(f, "ScrollFragmentPoint"),
             Msg::ChangeRunningAnimationsState(..) => write!(f, "ChangeRunningAnimationsState"),
             Msg::ChangePageTitle(..) => write!(f, "ChangePageTitle"),
-            Msg::ChangePageUrl(..) => write!(f, "ChangePageUrl"),
             Msg::SetFrameTree(..) => write!(f, "SetFrameTree"),
-            Msg::LoadComplete(..) => write!(f, "LoadComplete"),
+            Msg::LoadComplete => write!(f, "LoadComplete"),
             Msg::AllowNavigation(..) => write!(f, "AllowNavigation"),
-            Msg::LoadStart(..) => write!(f, "LoadStart"),
+            Msg::LoadStart => write!(f, "LoadStart"),
+            Msg::HistoryChanged(..) => write!(f, "HistoryChanged"),
             Msg::DelayedCompositionTimeout(..) => write!(f, "DelayedCompositionTimeout"),
             Msg::Recomposite(..) => write!(f, "Recomposite"),
             Msg::KeyEvent(..) => write!(f, "KeyEvent"),

components/compositing/windowing.rs

@@ -13,7 +13,7 @@ use euclid::size::TypedSize2D;
 use gleam::gl;
 use msg::constellation_msg::{Key, KeyModifiers, KeyState};
 use net_traits::net_error_list::NetError;
-use script_traits::{DevicePixel, MouseButton, TouchEventType, TouchId, TouchpadPressurePhase};
+use script_traits::{DevicePixel, LoadData, MouseButton, TouchEventType, TouchId, TouchpadPressurePhase};
 use servo_geometry::DeviceIndependentPixel;
 use servo_url::ServoUrl;
 use std::fmt::{Debug, Error, Formatter};
@@ -129,20 +129,20 @@ pub trait WindowMethods {
 
     /// Sets the page title for the current page.
     fn set_page_title(&self, title: Option<String>);
-    /// Sets the load data for the current page.
-    fn set_page_url(&self, url: ServoUrl);
     /// Called when the browser chrome should display a status message.
     fn status(&self, Option<String>);
     /// Called when the browser has started loading a frame.
-    fn load_start(&self, back: bool, forward: bool);
+    fn load_start(&self);
     /// Called when the browser is done loading a frame.
-    fn load_end(&self, back: bool, forward: bool, root: bool);
+    fn load_end(&self);
     /// Called when the browser encounters an error while loading a URL
     fn load_error(&self, code: NetError, url: String);
     /// Wether or not to follow a link
     fn allow_navigation(&self, url: ServoUrl) -> bool;
     /// Called when the <head> tag has finished parsing
     fn head_parsed(&self);
+    /// Called when the history state has changed.
+    fn history_changed(&self, Vec<LoadData>, usize);
 
     /// Returns the scale factor of the system (device pixels / device independent pixels).
     fn hidpi_factor(&self) -> ScaleFactor<f32, DeviceIndependentPixel, DevicePixel>;