libservo: Combine LoadStart, HeadParsed, and LoadComplete` messages (#35260)

These will be a single method in the upcoming `WebView` delegate, so it
makes sense to also combine the internal message to match this. In
addition, since `LoadStatus` is now exposed to the API if there is ever
the need to add more statuses or to move to an event-based version, the
API is already set up for this.

Signed-off-by: Martin Robinson <mrobinson@igalia.com>

ports/servoshell/egl/android.rs

@@ -15,7 +15,7 @@ use jni::objects::{GlobalRef, JClass, JObject, JString, JValue, JValueOwned};
 use jni::sys::{jboolean, jfloat, jint, jobject};
 use jni::{JNIEnv, JavaVM};
 use log::{debug, error, info, warn};
-use servo::MediaSessionActionType;
+use servo::{LoadStatus, MediaSessionActionType};
 use simpleservo::{
     DeviceIntRect, EventLoopWaker, InitOptions, InputMethodType, MediaSessionPlaybackState,
     PromptResult, SERVO,
@@ -496,18 +496,20 @@ impl HostTrait for HostCallbacks {
         Some(default)
     }
 
-    fn on_load_started(&self) {
-        debug!("on_load_started");
+    fn notify_load_status_changed(&self, load_status: LoadStatus) {
+        debug!("notify_load_status_changed: {load_status:?}");
         let mut env = self.jvm.get_env().unwrap();
-        env.call_method(self.callbacks.as_obj(), "onLoadStarted", "()V", &[])
-            .unwrap();
-    }
-
-    fn on_load_ended(&self) {
-        debug!("on_load_ended");
-        let mut env = self.jvm.get_env().unwrap();
-        env.call_method(self.callbacks.as_obj(), "onLoadEnded", "()V", &[])
-            .unwrap();
+        match load_status {
+            LoadStatus::Started => {
+                env.call_method(self.callbacks.as_obj(), "onLoadStarted", "()V", &[])
+                    .unwrap();
+            },
+            LoadStatus::HeadParsed => {},
+            LoadStatus::Complete => {
+                env.call_method(self.callbacks.as_obj(), "onLoadEnded", "()V", &[])
+                    .unwrap();
+            },
+        };
     }
 
     fn on_shutdown_complete(&self) {

ports/servoshell/egl/host_trait.rs

@@ -3,7 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 use servo::webrender_api::units::DeviceIntRect;
-use servo::{InputMethodType, MediaSessionPlaybackState, PromptResult};
+use servo::{InputMethodType, LoadStatus, MediaSessionPlaybackState, PromptResult};
 
 /// Callbacks. Implemented by embedder. Called by Servo.
 pub trait HostTrait {
@@ -17,16 +17,16 @@ pub trait HostTrait {
     fn prompt_input(&self, msg: String, default: String, trusted: bool) -> Option<String>;
     /// Show context menu
     fn show_context_menu(&self, title: Option<String>, items: Vec<String>);
-    /// Page starts loading.
-    /// "Reload button" should be disabled.
-    /// "Stop button" should be enabled.
-    /// Throbber starts spinning.
-    fn on_load_started(&self);
-    /// Page has loaded.
-    /// "Reload button" should be enabled.
-    /// "Stop button" should be disabled.
-    /// Throbber stops spinning.
-    fn on_load_ended(&self);
+    /// Notify that the load status of the page has changed.
+    /// Started:
+    ///  - "Reload button" should be disabled.
+    ///  - "Stop button" should be enabled.
+    ///  - Throbber starts spinning.
+    /// Complete:
+    ///  - "Reload button" should be enabled.
+    ///  - "Stop button" should be disabled.
+    ///  - Throbber stops spinning.
+    fn notify_load_status_changed(&self, load_status: LoadStatus);
     /// Page title has changed.
     fn on_title_changed(&self, title: Option<String>);
     /// Allow Navigation.

ports/servoshell/egl/ohos.rs

@@ -21,7 +21,7 @@ use napi_ohos::{Env, JsObject, JsString, NapiRaw};
 use ohos_ime::{AttachOptions, Ime, ImeProxy, RawTextEditorProxy};
 use ohos_ime_sys::types::InputMethod_EnterKeyType;
 use servo::style::Zero;
-use servo::{InputMethodType, MediaSessionPlaybackState, PromptResult};
+use servo::{InputMethodType, LoadStatus, MediaSessionPlaybackState, PromptResult};
 use simpleservo::EventLoopWaker;
 use xcomponent_sys::{
     OH_NativeXComponent, OH_NativeXComponent_Callback, OH_NativeXComponent_GetKeyEvent,
@@ -733,19 +733,17 @@ impl HostTrait for HostCallbacks {
         warn!("show_context_menu not implemented")
     }
 
-    fn on_load_started(&self) {
-        warn!("on_load_started not implemented")
-    }
-
-    fn on_load_ended(&self) {
-        // Note: It seems that we don't necessarily get 1 `on_load_ended` for each
-        // each time `on_loaded_started` is called. Presumably this requires some API changes,
+    fn notify_load_status_changed(&self, load_status: LoadStatus) {
+        // Note: It seems that we don't necessarily get 1 `LoadStatus::Complete` for each
+        // each time `LoadStatus::Started` is called. Presumably this requires some API changes,
         // e.g. including webview id, perhaps URL and some additional investigation effort.
         // For now we just add a trace event here, so that we can see in the trace if we
         // successfully loaded **a** page.
-        #[cfg(feature = "tracing-hitrace")]
-        let _scope = hitrace::ScopedTrace::start_trace(&c"PageLoadEndedPrompt");
-        self.prompt_alert("Page finished loading!".to_string(), true);
+        if load_status == LoadStatus::Complete {
+            #[cfg(feature = "tracing-hitrace")]
+            let _scope = hitrace::ScopedTrace::start_trace(&c"PageLoadEndedPrompt");
+            self.prompt_alert("Page finished loading!".to_string(), true);
+        }
     }
 
     fn on_title_changed(&self, title: Option<String>) {

ports/servoshell/egl/servo_glue.rs

@@ -479,11 +479,10 @@ impl ServoGlue {
                         .host_callbacks
                         .on_url_changed(entries[current].clone().to_string());
                 },
-                EmbedderMsg::LoadStart(_) => {
-                    self.callbacks.host_callbacks.on_load_started();
-                },
-                EmbedderMsg::LoadComplete(_) => {
-                    self.callbacks.host_callbacks.on_load_ended();
+                EmbedderMsg::NotifyLoadStatusChanged(_, load_status) => {
+                    self.callbacks
+                        .host_callbacks
+                        .notify_load_status_changed(load_status);
                 },
                 EmbedderMsg::GetSelectedBluetoothDevice(_, _, sender) => {
                     let _ = sender.send(None);
@@ -653,7 +652,6 @@ impl ServoGlue {
                 EmbedderMsg::MoveTo(..) |
                 EmbedderMsg::SetCursor(..) |
                 EmbedderMsg::NewFavicon(..) |
-                EmbedderMsg::HeadParsed(..) |
                 EmbedderMsg::SetFullscreenState(..) |
                 EmbedderMsg::ReportProfile(..) |
                 EmbedderMsg::EventDelivered(..) |