Auto merge of #12292 - ConnorGBrewster:runnable_variant, r=KiChjang

Consolidate runnable variants on DOMManipulationTask into a single Runnable variant.

<!-- Please describe your changes on the following line: -->
Consolidates the runnable variants on `DOMManipulationTask` into a single `Runnable` variant.
Also combines `MainThreadRunnable` into the `Runnable` trait.

I plan on filing a few E-Easy issues after this lands to implement `name` on each of the structs that implement `Runnable`.

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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

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components/script/dom/htmldetailselement.rs

@@ -79,7 +79,7 @@ impl VirtualMethods for HTMLDetailsElement {
                 element: details,
                 toggle_number: counter
             };
-            let _ = task_source.queue(DOMManipulationTask::FireToggleEvent(runnable));
+            let _ = task_source.queue(DOMManipulationTask::Runnable(runnable));
         }
     }
 }

components/script/dom/htmlformelement.rs

@@ -484,8 +484,7 @@ impl HTMLFormElement {
         };
 
         // Step 3
-        window.dom_manipulation_task_source().queue(
+        window.dom_manipulation_task_source().queue(DOMManipulationTask::Runnable(nav)).unwrap();
-            DOMManipulationTask::PlannedNavigation(nav)).unwrap();
     }
 
     /// Interactively validate the constraints of form elements

components/script/dom/htmlimageelement.rs

@@ -183,7 +183,7 @@ impl HTMLImageElement {
                         src: src.into(),
                     });
                     let task = window.dom_manipulation_task_source();
-                    let _ = task.queue(DOMManipulationTask::Miscellaneous(runnable));
+                    let _ = task.queue(DOMManipulationTask::Runnable(runnable));
                 }
             }
         }

components/script/dom/htmlmediaelement.rs

@@ -242,7 +242,7 @@ impl HTMLMediaElement {
             elem: Trusted::new(self),
         };
         let win = window_from_node(self);
-        let _ = win.dom_manipulation_task_source().queue(DOMManipulationTask::MediaTask(box task));
+        let _ = win.dom_manipulation_task_source().queue(DOMManipulationTask::Runnable(box task));
     }
 
     // https://html.spec.whatwg.org/multipage/#internal-pause-steps step 2.2
@@ -266,13 +266,13 @@ impl HTMLMediaElement {
             elem: Trusted::new(self),
         };
         let win = window_from_node(self);
-        let _ = win.dom_manipulation_task_source().queue(DOMManipulationTask::MediaTask(box task));
+        let _ = win.dom_manipulation_task_source().queue(DOMManipulationTask::Runnable(box task));
     }
 
     fn queue_fire_simple_event(&self, type_: &'static str) {
         let win = window_from_node(self);
         let task = FireSimpleEventTask::new(self, type_);
-        let _ = win.dom_manipulation_task_source().queue(DOMManipulationTask::MediaTask(box task));
+        let _ = win.dom_manipulation_task_source().queue(DOMManipulationTask::Runnable(box task));
     }
 
     fn fire_simple_event(&self, type_: &str) {
@@ -497,7 +497,7 @@ impl HTMLMediaElement {
 
     fn queue_dedicated_media_source_failure_steps(&self) {
         let _ = window_from_node(self).dom_manipulation_task_source().queue(
-            DOMManipulationTask::MediaTask(box DedicatedMediaSourceFailureTask::new(self)));
+            DOMManipulationTask::Runnable(box DedicatedMediaSourceFailureTask::new(self)));
     }
 
     // https://html.spec.whatwg.org/multipage/#dedicated-media-source-failure-steps

components/script/dom/storage.rs

@@ -17,7 +17,7 @@ use dom::urlhelper::UrlHelper;
 use ipc_channel::ipc::{self, IpcSender};
 use net_traits::IpcSend;
 use net_traits::storage_thread::{StorageThreadMsg, StorageType};
-use script_thread::{MainThreadRunnable, ScriptThread};
+use script_thread::{Runnable, ScriptThread};
 use task_source::TaskSource;
 use task_source::dom_manipulation::DOMManipulationTask;
 use url::Url;
@@ -161,7 +161,7 @@ impl Storage {
         let global_ref = global_root.r();
         let task_source = global_ref.as_window().dom_manipulation_task_source();
         let trusted_storage = Trusted::new(self);
-        task_source.queue(DOMManipulationTask::SendStorageNotification(
+        task_source.queue(DOMManipulationTask::Runnable(
             box StorageEventRunnable::new(trusted_storage, key, old_value, new_value))).unwrap();
     }
 }
@@ -180,8 +180,10 @@ impl StorageEventRunnable {
     }
 }
 
-impl MainThreadRunnable for StorageEventRunnable {
+impl Runnable for StorageEventRunnable {
-    fn handler(self: Box<StorageEventRunnable>, script_thread: &ScriptThread) {
+    fn name(&self) -> &'static str { "StorageEventRunnable" }
+
+    fn main_thread_handler(self: Box<StorageEventRunnable>, script_thread: &ScriptThread) {
         let this = *self;
         let storage_root = this.element.root();
         let storage = storage_root.r();

components/script/script_thread.rs

@@ -200,11 +200,9 @@ impl<T: Runnable + Send> Runnable for CancellableRunnable<T> {
 
 pub trait Runnable {
     fn is_cancelled(&self) -> bool { false }
-    fn handler(self: Box<Self>);
+    fn name(&self) -> &'static str { "generic runnable" }
-}
+    fn handler(self: Box<Self>) {}
-
+    fn main_thread_handler(self: Box<Self>, _script_thread: &ScriptThread) { self.handler(); }
-pub trait MainThreadRunnable {
-    fn handler(self: Box<Self>, script_thread: &ScriptThread);
 }
 
 enum MixedMessage {
@@ -1223,7 +1221,7 @@ impl ScriptThread {
 
         // https://html.spec.whatwg.org/multipage/#the-end step 7
         let handler = box DocumentProgressHandler::new(Trusted::new(doc));
-        self.dom_manipulation_task_source.queue(DOMManipulationTask::DocumentProgress(handler)).unwrap();
+        self.dom_manipulation_task_source.queue(DOMManipulationTask::Runnable(handler)).unwrap();
 
         self.constellation_chan.send(ConstellationMsg::LoadComplete(pipeline)).unwrap();
     }

components/script/task_source/dom_manipulation.rs

@@ -5,7 +5,7 @@
 use dom::bindings::refcounted::Trusted;
 use dom::event::{EventBubbles, EventCancelable};
 use dom::eventtarget::EventTarget;
-use script_thread::{MainThreadRunnable, MainThreadScriptMsg, Runnable, ScriptThread};
+use script_thread::{MainThreadScriptMsg, Runnable, ScriptThread};
 use std::result::Result;
 use std::sync::mpsc::Sender;
 use string_cache::Atom;
@@ -39,21 +39,12 @@ impl DOMManipulationTaskSource {
 }
 
 pub enum DOMManipulationTask {
-    // https://html.spec.whatwg.org/multipage/#the-end step 7
-    DocumentProgress(Box<Runnable + Send>),
     // https://dom.spec.whatwg.org/#concept-event-fire
     FireEvent(Trusted<EventTarget>, Atom, EventBubbles, EventCancelable),
     // https://html.spec.whatwg.org/multipage/#fire-a-simple-event
     FireSimpleEvent(Trusted<EventTarget>, Atom),
-    // https://html.spec.whatwg.org/multipage/#details-notification-task-steps
+
-    FireToggleEvent(Box<Runnable + Send>),
+    Runnable(Box<Runnable + Send>),
-    // Placeholder until there's a real media element task queue implementation
-    MediaTask(Box<Runnable + Send>),
-    // https://html.spec.whatwg.org/multipage/#planned-navigation
-    PlannedNavigation(Box<Runnable + Send>),
-    // https://html.spec.whatwg.org/multipage/#send-a-storage-notification
-    SendStorageNotification(Box<MainThreadRunnable + Send>),
-    Miscellaneous(Box<Runnable + Send>),
 }
 
 impl DOMManipulationTask {
@@ -61,7 +52,6 @@ impl DOMManipulationTask {
         use self::DOMManipulationTask::*;
 
         match self {
-            DocumentProgress(runnable) => runnable.handler(),
             FireEvent(element, name, bubbles, cancelable) => {
                 let target = element.root();
                 target.fire_event(&*name, bubbles, cancelable);
@@ -70,11 +60,11 @@ impl DOMManipulationTask {
                 let target = element.root();
                 target.fire_simple_event(&*name);
             }
-            FireToggleEvent(runnable) => runnable.handler(),
+            Runnable(runnable) => {
-            MediaTask(runnable) => runnable.handler(),
+                if !runnable.is_cancelled() {
-            PlannedNavigation(runnable) => runnable.handler(),
+                    runnable.main_thread_handler(script_thread);
-            SendStorageNotification(runnable) => runnable.handler(script_thread),
+                }
-            Miscellaneous(runnable) => runnable.handler(),
+            }
         }
     }
 }