LibWeb: Avoid invoking Trusted Types where avoidable

Prevents observably calling Trusted Types, which can run arbitrary JS,
cause crashes due to use of MUST and allow arbitrary JS to modify
internal elements.

Libraries/LibWeb/HTML/HTMLMediaElement.cpp

@@ -68,7 +68,7 @@ void HTMLMediaElement::initialize(JS::Realm& realm)
     m_document_observer->set_document_became_inactive([this]() {
         // If the media element's node document stops being a fully active document, then the playback will stop until
         // the document is active again.
-        pause_element().release_value_but_fixme_should_propagate_errors();
+        pause_element();
     });
 
     document().page().register_media_element({}, unique_id());
@@ -136,7 +136,7 @@ void HTMLMediaElement::removed_from(DOM::Node* old_parent, DOM::Node& old_root)
         return;
 
     // 3. ⌛ Run the internal pause steps for the media element.
-    pause_element().release_value_but_fixme_should_propagate_errors();
+    pause_element();
 }
 
 // https://html.spec.whatwg.org/multipage/media.html#fatal-decode-error
@@ -369,7 +369,7 @@ void HTMLMediaElement::set_duration(double duration)
         paintable->set_needs_display();
 }
 
-WebIDL::ExceptionOr<GC::Ref<WebIDL::Promise>> HTMLMediaElement::play()
+GC::Ref<WebIDL::Promise> HTMLMediaElement::play()
 {
     auto& realm = this->realm();
 
@@ -387,37 +387,33 @@ WebIDL::ExceptionOr<GC::Ref<WebIDL::Promise>> HTMLMediaElement::play()
     m_pending_play_promises.append(promise);
 
     // 4. Run the internal play steps for the media element.
-    TRY(play_element());
+    play_element();
 
     // 5. Return promise.
     return promise;
 }
 
 // https://html.spec.whatwg.org/multipage/media.html#dom-media-pause
-WebIDL::ExceptionOr<void> HTMLMediaElement::pause()
+void HTMLMediaElement::pause()
 {
     // 1. If the media element's networkState attribute has the value NETWORK_EMPTY, invoke the media element's resource
     //    selection algorithm.
     if (m_network_state == NetworkState::Empty)
-        TRY(select_resource());
+        select_resource();
 
     // 2. Run the internal pause steps for the media element.
-    TRY(pause_element());
-
-    return {};
+    pause_element();
 }
 
-WebIDL::ExceptionOr<void> HTMLMediaElement::toggle_playback()
+void HTMLMediaElement::toggle_playback()
 {
     // AD-HOC: An execution context is required for Promise creation hooks.
     TemporaryExecutionContext execution_context { realm() };
 
     if (potentially_playing())
-        TRY(pause());
+        pause();
     else
-        TRY(play());
-
-    return {};
+        play();
 }
 
 // https://html.spec.whatwg.org/multipage/media.html#dom-media-volume
@@ -628,7 +624,7 @@ WebIDL::ExceptionOr<void> HTMLMediaElement::load_element()
     m_can_autoplay = true;
 
     // 9. Invoke the media element's resource selection algorithm.
-    TRY(select_resource());
+    select_resource();
 
     // 10. NOTE: Playback of any previously playing media resource for this element stops.
     return {};
@@ -825,7 +821,7 @@ void HTMLMediaElement::children_changed(ChildrenChangedMetadata const* metadata)
 }
 
 // https://html.spec.whatwg.org/multipage/media.html#concept-media-load-algorithm
-WebIDL::ExceptionOr<void> HTMLMediaElement::select_resource()
+void HTMLMediaElement::select_resource()
 {
     auto& realm = this->realm();
 
@@ -972,8 +968,6 @@ WebIDL::ExceptionOr<void> HTMLMediaElement::select_resource()
             break;
         }
     });
-
-    return {};
 }
 
 enum class FetchMode {
@@ -1592,12 +1586,12 @@ void HTMLMediaElement::on_playback_manager_state_change()
 }
 
 // https://html.spec.whatwg.org/multipage/media.html#internal-play-steps
-WebIDL::ExceptionOr<void> HTMLMediaElement::play_element()
+void HTMLMediaElement::play_element()
 {
     // 1. If the media element's networkState attribute has the value NETWORK_EMPTY, invoke the media element's resource
     //    selection algorithm.
     if (m_network_state == NetworkState::Empty)
-        TRY(select_resource());
+        select_resource();
 
     // 2. If the playback has ended and the direction of playback is forwards, seek to the earliest possible position
     //    of the media resource.
@@ -1654,12 +1648,10 @@ WebIDL::ExceptionOr<void> HTMLMediaElement::play_element()
 
     // 5. Set the media element's can autoplay flag to false.
     m_can_autoplay = false;
-
-    return {};
 }
 
 // https://html.spec.whatwg.org/multipage/media.html#internal-pause-steps
-WebIDL::ExceptionOr<void> HTMLMediaElement::pause_element()
+void HTMLMediaElement::pause_element()
 {
     // 1. Set the media element's can autoplay flag to false.
     m_can_autoplay = false;
@@ -1689,8 +1681,6 @@ WebIDL::ExceptionOr<void> HTMLMediaElement::pause_element()
         // 4. Set the official playback position to the current playback position.
         m_official_playback_position = m_current_playback_position;
     }
-
-    return {};
 }
 
 // https://html.spec.whatwg.org/multipage/media.html#dom-media-seek
@@ -2217,14 +2207,14 @@ void HTMLMediaElement::reject_pending_play_promises(ReadonlySpan<GC::Ref<WebIDL:
         WebIDL::reject_promise(realm, promise, error);
 }
 
-WebIDL::ExceptionOr<bool> HTMLMediaElement::handle_keydown(Badge<Web::EventHandler>, UIEvents::KeyCode key, u32 modifiers)
+bool HTMLMediaElement::handle_keydown(Badge<Web::EventHandler>, UIEvents::KeyCode key, u32 modifiers)
 {
     if (modifiers != UIEvents::KeyModifier::Mod_None)
         return false;
 
     switch (key) {
     case UIEvents::KeyCode::Key_Space:
-        TRY(toggle_playback());
+        toggle_playback();
         break;
 
     case UIEvents::KeyCode::Key_Home:
@@ -2258,7 +2248,8 @@ WebIDL::ExceptionOr<bool> HTMLMediaElement::handle_keydown(Badge<Web::EventHandl
         else
             volume = max(0.0, volume - volume_change_per_key_press);
 
-        TRY(set_volume(volume));
+        // This should never fail since volume is clamped to 0.0..1.0 above.
+        MUST(set_volume(volume));
         break;
     }