Auto merge of #18804 - servo:media, r=emilio

Another couple of low-key media improvements 👶👣

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components/script/dom/htmlmediaelement.rs

@@ -20,6 +20,7 @@ use dom::bindings::refcounted::Trusted;
 use dom::bindings::reflector::DomObject;
 use dom::bindings::root::{DomRoot, MutNullableDom};
 use dom::bindings::str::DOMString;
+use dom::blob::Blob;
 use dom::document::Document;
 use dom::element::{Element, AttributeMutation};
 use dom::eventtarget::EventTarget;
@@ -57,6 +58,8 @@ pub struct HTMLMediaElement {
     network_state: Cell<NetworkState>,
     /// https://html.spec.whatwg.org/multipage/#dom-media-readystate
     ready_state: Cell<ReadyState>,
+    /// https://html.spec.whatwg.org/multipage/#dom-media-srcobject
+    src_object: MutNullableDom<Blob>,
     /// https://html.spec.whatwg.org/multipage/#dom-media-currentsrc
     current_src: DomRefCell<String>,
     /// Incremented whenever tasks associated with this element are cancelled.
@@ -112,6 +115,7 @@ impl HTMLMediaElement {
             htmlelement: HTMLElement::new_inherited(tag_name, prefix, document),
             network_state: Cell::new(NetworkState::Empty),
             ready_state: Cell::new(ReadyState::HaveNothing),
+            src_object: Default::default(),
             current_src: DomRefCell::new("".to_owned()),
             generation_id: Cell::new(0),
             fired_loadeddata_event: Cell::new(false),
@@ -430,6 +434,7 @@ impl HTMLMediaElement {
         let doc = document_from_node(self);
         let task = MediaElementMicrotask::ResourceSelectionTask {
             elem: DomRoot::from_ref(self),
+            generation_id: self.generation_id.get(),
             base_url: doc.base_url()
         };
 
@@ -447,13 +452,14 @@ impl HTMLMediaElement {
 
         // Step 6.
         enum Mode {
-            // FIXME(nox): Support media object provider.
-            #[allow(dead_code)]
             Object,
             Attribute(String),
             Children(DomRoot<HTMLSourceElement>),
         }
         fn mode(media: &HTMLMediaElement) -> Option<Mode> {
+            if media.src_object.get().is_some() {
+                return Some(Mode::Object);
+            }
             if let Some(attr) = media.upcast::<Element>().get_attribute(&ns!(), &local_name!("src")) {
                 return Some(Mode::Attribute(attr.Value().into()));
             }
@@ -499,7 +505,6 @@ impl HTMLMediaElement {
                 // Step 9.obj.3.
                 // Note that the resource fetch algorithm itself takes care
                 // of the cleanup in case of failure itself.
-                // FIXME(nox): Pass the assigned media provider here.
                 self.resource_fetch_algorithm(Resource::Object);
             },
             Mode::Attribute(src) => {
@@ -612,7 +617,7 @@ impl HTMLMediaElement {
                 document.loader().fetch_async_background(request, action_sender);
             },
             Resource::Object => {
-                // FIXME(nox): Use the current media resource.
+                // FIXME(nox): Actually do something with the object.
                 self.queue_dedicated_media_source_failure_steps();
             },
         }
@@ -672,12 +677,10 @@ impl HTMLMediaElement {
         // this invokation of the load algorithm.
         self.fired_loadeddata_event.set(false);
 
-        // Step 1.
+        // Step 1-2.
-        // FIXME(nox): Abort any already-running instance of the
-        // resource selection algorithm.
-
-        // Steps 2-4.
         self.generation_id.set(self.generation_id.get() + 1);
+
+        // Steps 3-4.
         while !self.in_flight_play_promises_queue.borrow().is_empty() {
             self.fulfill_in_flight_play_promises(|| ());
         }
@@ -837,6 +840,17 @@ impl HTMLMediaElementMethods for HTMLMediaElement {
     // https://html.spec.whatwg.org/multipage/#dom-media-src
     make_setter!(SetSrc, "src");
 
+    // https://html.spec.whatwg.org/multipage/#dom-media-srcobject
+    fn GetSrcObject(&self) -> Option<DomRoot<Blob>> {
+        self.src_object.get()
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-media-srcobject
+    fn SetSrcObject(&self, value: Option<&Blob>) {
+        self.src_object.set(value);
+        self.media_element_load_algorithm();
+    }
+
     // https://html.spec.whatwg.org/multipage/#attr-media-preload
     // Missing value default is user-agent defined.
     make_enumerated_getter!(Preload, "preload", "", "none" | "metadata" | "auto");
@@ -929,7 +943,8 @@ impl VirtualMethods for HTMLMediaElement {
 pub enum MediaElementMicrotask {
     ResourceSelectionTask {
         elem: DomRoot<HTMLMediaElement>,
-        base_url: ServoUrl
+        generation_id: u32,
+        base_url: ServoUrl,
     },
     PauseIfNotInDocumentTask {
         elem: DomRoot<HTMLMediaElement>,
@@ -939,8 +954,10 @@ pub enum MediaElementMicrotask {
 impl MicrotaskRunnable for MediaElementMicrotask {
     fn handler(&self) {
         match self {
-            &MediaElementMicrotask::ResourceSelectionTask { ref elem, ref base_url } => {
+            &MediaElementMicrotask::ResourceSelectionTask { ref elem, generation_id, ref base_url } => {
+                if generation_id == elem.generation_id.get() {
                     elem.resource_selection_algorithm_sync(base_url.clone());
+                }
             },
             &MediaElementMicrotask::PauseIfNotInDocumentTask { ref elem } => {
                 if !elem.upcast::<Node>().is_in_doc() {

components/script/dom/webidls/HTMLMediaElement.webidl

@@ -3,25 +3,26 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 // https://html.spec.whatwg.org/multipage/#htmlmediaelement
+
 enum CanPlayTypeResult { "" /* empty string */, "maybe", "probably" };
+typedef /* (MediaStream or MediaSource or */ Blob /* ) */ MediaProvider;
+
 [Abstract]
 interface HTMLMediaElement : HTMLElement {
   // error state
   readonly attribute MediaError? error;
 
   // network state
-  [CEReactions]
+  [CEReactions] attribute DOMString src;
-           attribute DOMString src;
+  attribute MediaProvider? srcObject;
   readonly attribute DOMString currentSrc;
-  // [CEReactions]
+  // [CEReactions] attribute DOMString crossOrigin;
-  //          attribute DOMString crossOrigin;
   const unsigned short NETWORK_EMPTY = 0;
   const unsigned short NETWORK_IDLE = 1;
   const unsigned short NETWORK_LOADING = 2;
   const unsigned short NETWORK_NO_SOURCE = 3;
   readonly attribute unsigned short networkState;
-  [CEReactions]
+  [CEReactions] attribute DOMString preload;
-           attribute DOMString preload;
   // readonly attribute TimeRanges buffered;
   void load();
   CanPlayTypeResult canPlayType(DOMString type);
@@ -46,24 +47,16 @@ interface HTMLMediaElement : HTMLElement {
   // readonly attribute TimeRanges played;
   // readonly attribute TimeRanges seekable;
   // readonly attribute boolean ended;
-  [CEReactions]
+  [CEReactions] attribute boolean autoplay;
-           attribute boolean autoplay;
+  // [CEReactions] attribute boolean loop;
-  // [CEReactions]
-  //          attribute boolean loop;
   Promise<void> play();
   void pause();
 
-  // media controller
-  //          attribute DOMString mediaGroup;
-  //          attribute MediaController? controller;
-
   // controls
-  // [CEReactions]
+  // [CEReactions] attribute boolean controls;
-  //          attribute boolean controls;
   // attribute double volume;
   // attribute boolean muted;
-  // [CEReactions]
+  // [CEReactions] attribute boolean defaultMuted;
-  //          attribute boolean defaultMuted;
 
   // tracks
   // readonly attribute AudioTrackList audioTracks;