LibWeb: Align session history step application code with latest spec

Replaces direct "apply the history step" calls with new functions from
the spec:
- "update for navigable creation/destruction"
- "apply the push/replace history step"
- "apply the reload history step"

Userland/Libraries/LibWeb/HTML/Navigable.cpp

@@ -1293,8 +1293,8 @@ void Navigable::reload()
 
     // 3. Append the following session history traversal steps to traversable:
     traversable->append_session_history_traversal_steps([traversable] {
-        // 1. Apply pending history changes to traversable with true.
+        // 1. Apply the reload history step to traversable.
-        traversable->apply_pending_history_changes();
+        traversable->apply_the_reload_history_step();
     });
 }
 
@@ -1438,8 +1438,8 @@ void finalize_a_cross_document_navigation(JS::NonnullGCPtr<Navigable> navigable,
         target_step = traversable->current_session_history_step();
     }
 
-    // FIXME: 10. Apply the push/replace history step targetStep to traversable.
+    // 10. Apply the push/replace history step targetStep to traversable.
-    traversable->apply_the_history_step(target_step);
+    traversable->apply_the_push_or_replace_history_step(target_step);
 }
 
 // https://html.spec.whatwg.org/multipage/browsing-the-web.html#url-and-history-update-steps

Userland/Libraries/LibWeb/HTML/NavigableContainer.cpp

@@ -126,7 +126,8 @@ WebIDL::ExceptionOr<void> NavigableContainer::create_new_child_navigable()
         // 5. Append nestedHistory to parentDocState's nested histories.
         parent_doc_state->nested_histories().append(move(nested_history));
 
-        // FIXME: 6. Update for navigable creation/destruction given traversable
+        // 6. Update for navigable creation/destruction given traversable
+        traversable->update_for_navigable_creation_or_destruction();
     });
 
     return {};
@@ -336,7 +337,7 @@ void NavigableContainer::destroy_the_child_navigable()
     // 8. Append the following session history traversal steps to traversable:
     traversable->append_session_history_traversal_steps([traversable] {
         // 1. Apply pending history changes to traversable.
-        traversable->apply_pending_history_changes();
+        traversable->update_for_navigable_creation_or_destruction();
     });
 }
 

Userland/Libraries/LibWeb/HTML/TraversableNavigable.cpp

@@ -498,14 +498,34 @@ void TraversableNavigable::traverse_the_history_by_delta(int delta)
     });
 }
 
-// https://html.spec.whatwg.org/multipage/browsing-the-web.html#apply-pending-history-changes
+// https://html.spec.whatwg.org/multipage/browsing-the-web.html#update-for-navigable-creation/destruction
-void TraversableNavigable::apply_pending_history_changes()
+void TraversableNavigable::update_for_navigable_creation_or_destruction()
 {
-    // 1. Let targetStep be traversable's current session history step.
+    // 1. Let step be traversable's current session history step.
-    auto target_step = current_session_history_step();
+    auto step = current_session_history_step();
 
-    // 2. Apply the history step targetStep to traversable with checkForUserCancelation set to checkForUserCancelation.
+    // 2. Return the result of applying the history step step to traversable given false, false, null, null, and null.
-    apply_the_history_step(target_step);
+    // FIXME: Pass false, false, null, null, and null as arguments.
+    apply_the_history_step(step);
+}
+
+// https://html.spec.whatwg.org/multipage/browsing-the-web.html#apply-the-reload-history-step
+void TraversableNavigable::apply_the_reload_history_step()
+{
+    // 1. Let step be traversable's current session history step.
+    auto step = current_session_history_step();
+
+    // 2. Return the result of applying the history step step to traversable given true, false, null, null, and null.
+    // FIXME: Pass true, false, null, null, and null as arguments.
+    apply_the_history_step(step);
+}
+
+void TraversableNavigable::apply_the_push_or_replace_history_step(int step)
+{
+    // 1. Return the result of applying the history step step to traversable given false, false, null, null, and null.
+    // FIXME: Pass false, false, null, null, and null as arguments.
+    // FIXME: Return result of history application.
+    apply_the_history_step(step);
 }
 
 // https://html.spec.whatwg.org/multipage/document-sequences.html#close-a-top-level-traversable
@@ -595,7 +615,7 @@ void finalize_a_same_document_navigation(JS::NonnullGCPtr<TraversableNavigable>
     }
 
     // 6. Apply the push/replace history step targetStep to traversable.
-    traversable->apply_the_history_step(*target_step);
+    traversable->apply_the_push_or_replace_history_step(*target_step);
 }
 
 }

Userland/Libraries/LibWeb/HTML/TraversableNavigable.h

@@ -37,8 +37,9 @@ public:
     };
     HistoryObjectLengthAndIndex get_the_history_object_length_and_index(int) const;
 
-    void apply_the_history_step(int step, Optional<SourceSnapshotParams> = {});
+    void apply_the_reload_history_step();
-    void apply_pending_history_changes();
+    void apply_the_push_or_replace_history_step(int step);
+    void update_for_navigable_creation_or_destruction();
 
     int get_the_used_step(int step) const;
     Vector<JS::Handle<Navigable>> get_all_navigables_whose_current_session_history_entry_will_change_or_reload(int) const;
@@ -62,6 +63,8 @@ private:
 
     virtual void visit_edges(Cell::Visitor&) override;
 
+    void apply_the_history_step(int step, Optional<SourceSnapshotParams> = {});
+
     // https://html.spec.whatwg.org/multipage/document-sequences.html#tn-current-session-history-step
     int m_current_session_history_step { 0 };