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`.

---
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- [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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5 files changed, 13 insertions, 12 deletions

diff --git a/components/script/dom/htmldetailselement.rs b/components/script/dom/htmldetailselement.rs
index d63e15178aa..07c85ed6e2e 100644
--- a/components/script/dom/htmldetailselement.rs
+++ b/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));
         }
     }
 }
diff --git a/components/script/dom/htmlformelement.rs b/components/script/dom/htmlformelement.rs
index b31d33d5685..90baba4ebb1 100644
--- a/components/script/dom/htmlformelement.rs
+++ b/components/script/dom/htmlformelement.rs
@@ -484,8 +484,7 @@ impl HTMLFormElement {
         };
 
         // Step 3
-        window.dom_manipulation_task_source().queue(
-            DOMManipulationTask::PlannedNavigation(nav)).unwrap();
+        window.dom_manipulation_task_source().queue(DOMManipulationTask::Runnable(nav)).unwrap();
     }
 
     /// Interactively validate the constraints of form elements
diff --git a/components/script/dom/htmlimageelement.rs b/components/script/dom/htmlimageelement.rs
index 2b61a800a1a..27152ca93f4 100644
--- a/components/script/dom/htmlimageelement.rs
+++ b/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));
                 }
             }
         }
diff --git a/components/script/dom/htmlmediaelement.rs b/components/script/dom/htmlmediaelement.rs
index 49d42c31f1a..7cfe19ba789 100644
--- a/components/script/dom/htmlmediaelement.rs
+++ b/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
diff --git a/components/script/dom/storage.rs b/components/script/dom/storage.rs
index 03747ed5ab6..d927c5ba213 100644
--- a/components/script/dom/storage.rs
+++ b/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 {
-    fn handler(self: Box<StorageEventRunnable>, script_thread: &ScriptThread) {
+impl Runnable for StorageEventRunnable {
+    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();