Fire UIA SelectionItem events on aria-checked changes for radio buttons

According to the following spec radio and menuitemradio should expose
UIA SelectedItem.IsSelected when aria-checked is set :
https://www.w3.org/TR/core-aam-1.1/#mapping_state-property_table

This CL ensures that radio / menuitemradio fire appropriate
SelectionItem events, and whenever a SelectionItem changes its
selection state that we also fire a Property Changed event for
SelectionItem.IsSelected.

AX-Relnotes: Fire missing events for ARIA radio/menuitemradio when aria-checked changes. Narrator will now announce selected state changes for this scenario.
Bug: 1102580
Change-Id: I72f479e25f61b0ddffc28f73d4a9c34e8dc4ecb8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2212982Reviewed-by: Nektarios Paisios <nektar@chromium.org>
Reviewed-by: Kevin Babbitt <kbabbitt@microsoft.com>
Commit-Queue: Adam Ettenberger <Adam.Ettenberger@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#791802}

content/browser/accessibility/browser_accessibility_manager_win.cc

@@ -157,6 +157,13 @@ void BrowserAccessibilityManagerWin::FireGeneratedEvent(
       aria_properties_events_.insert(node);
       break;
     case ui::AXEventGenerator::Event::CHECKED_STATE_CHANGED:
+      // https://www.w3.org/TR/core-aam-1.1/#mapping_state-property_table
+      // SelectionItem.IsSelected is set according to the True or False value of
+      // aria-checked for 'radio' and 'menuitemradio' roles.
+      if (ui::IsRadio(node->GetRole())) {
+        HandleSelectedStateChanged(uia_selection_events_, node,
+                                   IsUIANodeSelected(node));
+      }
       FireUiaPropertyChangedEvent(UIA_ToggleToggleStatePropertyId, node);
       aria_properties_events_.insert(node);
       break;
@@ -328,7 +335,10 @@ void BrowserAccessibilityManagerWin::FireGeneratedEvent(
                                   node);
       break;
     case ui::AXEventGenerator::Event::SELECTED_CHANGED:
-      HandleSelectedStateChanged(node);
+      HandleSelectedStateChanged(ia2_selection_events_, node,
+                                 IsIA2NodeSelected(node));
+      HandleSelectedStateChanged(uia_selection_events_, node,
+                                 IsUIANodeSelected(node));
       aria_properties_events_.insert(node);
       break;
     case ui::AXEventGenerator::Event::SELECTED_CHILDREN_CHANGED:
@@ -646,34 +656,144 @@ void BrowserAccessibilityManagerWin::OnAtomicUpdateFinished(
   }
 }
 
-void BrowserAccessibilityManagerWin::HandleSelectedStateChanged(
+// static
+bool BrowserAccessibilityManagerWin::IsIA2NodeSelected(
     BrowserAccessibility* node) {
-  const bool is_selected =
-      node->GetBoolAttribute(ax::mojom::BoolAttribute::kSelected);
-
-  // Nodes that have selection container may support multiselect, for such nodes
-  // we add them to |selection_events_|, which FinalizeAccessibilityEvents
-  // handles selection item events firing.
-  // For nodes that do not have selection container, only single select is
-  // supported, selection item events firing are handled here.
-  if (auto* selection_container = node->PlatformGetSelectionContainer()) {
-    if (is_selected) {
-      selection_events_[selection_container].added.push_back(node);
-    } else {
-      selection_events_[selection_container].removed.push_back(node);
+  return node->GetBoolAttribute(ax::mojom::BoolAttribute::kSelected);
+}
+
+// static
+bool BrowserAccessibilityManagerWin::IsUIANodeSelected(
+    BrowserAccessibility* node) {
+  // https://www.w3.org/TR/core-aam-1.1/#mapping_state-property_table
+  // SelectionItem.IsSelected is set according to the True or False value of
+  // aria-checked for 'radio' and 'menuitemradio' roles.
+  if (ui::IsRadio(node->GetRole()))
+    return node->GetData().GetCheckedState() == ax::mojom::CheckedState::kTrue;
+
+  return node->GetBoolAttribute(ax::mojom::BoolAttribute::kSelected);
+}
+
+void BrowserAccessibilityManagerWin::FireIA2SelectionEvents(
+    BrowserAccessibility* container,
+    BrowserAccessibility* only_selected_child,
+    const SelectionEvents& changes) {
+  if (only_selected_child) {
+    // Fire 'ElementSelected' on the only selected child.
+    FireWinAccessibilityEvent(EVENT_OBJECT_SELECTION, only_selected_child);
+  } else {
+    const bool container_is_multiselectable =
+        container && container->HasState(ax::mojom::State::kMultiselectable);
+    for (auto* item : changes.added) {
+      if (container_is_multiselectable)
+        FireWinAccessibilityEvent(EVENT_OBJECT_SELECTIONADD, item);
+      else
+        FireWinAccessibilityEvent(EVENT_OBJECT_SELECTION, item);
     }
+    for (auto* item : changes.removed)
+      FireWinAccessibilityEvent(EVENT_OBJECT_SELECTIONREMOVE, item);
+  }
+}
+
+void BrowserAccessibilityManagerWin::FireUIASelectionEvents(
+    BrowserAccessibility* container,
+    BrowserAccessibility* only_selected_child,
+    const SelectionEvents& changes) {
+  if (only_selected_child) {
+    // Fire 'ElementSelected' on the only selected child.
+    FireUiaAccessibilityEvent(UIA_SelectionItem_ElementSelectedEventId,
+                              only_selected_child);
+    FireUiaPropertyChangedEvent(UIA_SelectionItemIsSelectedPropertyId,
+                                only_selected_child);
+    for (auto* item : changes.removed)
+      FireUiaPropertyChangedEvent(UIA_SelectionItemIsSelectedPropertyId, item);
   } else {
-    if (is_selected) {
-      FireWinAccessibilityEvent(EVENT_OBJECT_SELECTION, node);
-      FireUiaAccessibilityEvent(UIA_SelectionItem_ElementSelectedEventId, node);
+    // Per UIA documentation, beyond the "invalidate limit" we're supposed to
+    // fire a 'SelectionInvalidated' event.  The exact value isn't specified,
+    // but System.Windows.Automation.Provider uses a value of 20.
+    static const size_t kInvalidateLimit = 20;
+    if ((changes.added.size() + changes.removed.size()) > kInvalidateLimit) {
+      DCHECK_NE(container, nullptr);
+      FireUiaAccessibilityEvent(UIA_Selection_InvalidatedEventId, container);
     } else {
-      FireWinAccessibilityEvent(EVENT_OBJECT_SELECTIONREMOVE, node);
-      FireUiaAccessibilityEvent(
-          UIA_SelectionItem_ElementRemovedFromSelectionEventId, node);
+      const bool container_is_multiselectable =
+          container && container->HasState(ax::mojom::State::kMultiselectable);
+      for (auto* item : changes.added) {
+        if (container_is_multiselectable) {
+          FireUiaAccessibilityEvent(
+              UIA_SelectionItem_ElementAddedToSelectionEventId, item);
+        } else {
+          FireUiaAccessibilityEvent(UIA_SelectionItem_ElementSelectedEventId,
+                                    item);
+        }
+        FireUiaPropertyChangedEvent(UIA_SelectionItemIsSelectedPropertyId,
+                                    item);
+      }
+      for (auto* item : changes.removed) {
+        FireUiaAccessibilityEvent(
+            UIA_SelectionItem_ElementRemovedFromSelectionEventId, item);
+        FireUiaPropertyChangedEvent(UIA_SelectionItemIsSelectedPropertyId,
+                                    item);
+      }
     }
   }
 }
 
+// static
+void BrowserAccessibilityManagerWin::HandleSelectedStateChanged(
+    SelectionEventsMap& selection_events_map,
+    BrowserAccessibility* node,
+    bool is_selected) {
+  // If |node| belongs to a selection container, then map the events with the
+  // selection container as the key because |FinalizeSelectionEvents| needs to
+  // determine whether or not there is only one element selected in order to
+  // optimize what platform events are sent.
+  BrowserAccessibility* key = node;
+  if (auto* selection_container = node->PlatformGetSelectionContainer())
+    key = selection_container;
+
+  if (is_selected)
+    selection_events_map[key].added.push_back(node);
+  else
+    selection_events_map[key].removed.push_back(node);
+}
+
+// static
+void BrowserAccessibilityManagerWin::FinalizeSelectionEvents(
+    SelectionEventsMap& selection_events_map,
+    IsSelectedPredicate is_selected_predicate,
+    FirePlatformSelectionEventsCallback fire_platform_events_callback) {
+  for (auto&& selected : selection_events_map) {
+    BrowserAccessibility* key_node = selected.first;
+    SelectionEvents& changes = selected.second;
+
+    // Determine if |node| is a selection container with one selected child in
+    // order to optimize what platform events are sent.
+    BrowserAccessibility* container = nullptr;
+    BrowserAccessibility* only_selected_child = nullptr;
+    if (ui::IsContainerWithSelectableChildren(key_node->GetRole())) {
+      container = key_node;
+      for (auto it = container->InternalChildrenBegin();
+           it != container->InternalChildrenEnd(); ++it) {
+        auto* child = it.get();
+        if (is_selected_predicate.Run(child)) {
+          if (!only_selected_child) {
+            only_selected_child = child;
+            continue;
+          }
+
+          only_selected_child = nullptr;
+          break;
+        }
+      }
+    }
+
+    fire_platform_events_callback.Run(container, only_selected_child, changes);
+  }
+
+  selection_events_map.clear();
+}
+
 void BrowserAccessibilityManagerWin::BeforeAccessibilityEvents() {
   BrowserAccessibilityManager::BeforeAccessibilityEvents();
 
@@ -710,56 +830,17 @@ void BrowserAccessibilityManagerWin::FinalizeAccessibilityEvents() {
   text_selection_changed_events_.clear();
 
   // Finalize selection item events.
-  for (auto&& selected : selection_events_) {
-    auto* container = selected.first;
-    auto&& changes = selected.second;
-
-    // Count the number of selected items
-    size_t selected_count = 0;
-    BrowserAccessibility* first_selected_child = nullptr;
-    for (auto it = container->InternalChildrenBegin();
-         it != container->InternalChildrenEnd(); ++it) {
-      auto* child = it.get();
-      if (child->GetBoolAttribute(ax::mojom::BoolAttribute::kSelected)) {
-        if (!first_selected_child)
-          first_selected_child = child;
-        selected_count++;
-      }
-    }
+  FinalizeSelectionEvents(
+      ia2_selection_events_, base::BindRepeating(&IsIA2NodeSelected),
+      base::BindRepeating(
+          &BrowserAccessibilityManagerWin::FireIA2SelectionEvents,
+          base::Unretained(this)));
+  FinalizeSelectionEvents(
+      uia_selection_events_, base::BindRepeating(&IsUIANodeSelected),
+      base::BindRepeating(
+          &BrowserAccessibilityManagerWin::FireUIASelectionEvents,
+          base::Unretained(this)));
 
-    if (selected_count == 1) {
-      // Fire 'ElementSelected' on the only selected child
-      FireWinAccessibilityEvent(EVENT_OBJECT_SELECTION, first_selected_child);
-      FireUiaAccessibilityEvent(UIA_SelectionItem_ElementSelectedEventId,
-                                first_selected_child);
-    } else {
-      // Per UIA documentation, beyond the "invalidate limit" we're supposed to
-      // fire a 'SelectionInvalidated' event.  The exact value isn't specified,
-      // but System.Windows.Automation.Provider uses a value of 20.
-      static const size_t kInvalidateLimit = 20;
-      if ((changes.added.size() + changes.removed.size()) > kInvalidateLimit) {
-        FireUiaAccessibilityEvent(UIA_Selection_InvalidatedEventId, container);
-      } else {
-        for (auto* item : changes.added) {
-          if (container->HasState(ax::mojom::State::kMultiselectable)) {
-            FireWinAccessibilityEvent(EVENT_OBJECT_SELECTIONADD, item);
-            FireUiaAccessibilityEvent(
-                UIA_SelectionItem_ElementAddedToSelectionEventId, item);
-          } else {
-            FireWinAccessibilityEvent(EVENT_OBJECT_SELECTION, item);
-            FireUiaAccessibilityEvent(UIA_SelectionItem_ElementSelectedEventId,
-                                      item);
-          }
-        }
-        for (auto* item : changes.removed) {
-          FireWinAccessibilityEvent(EVENT_OBJECT_SELECTIONREMOVE, item);
-          FireUiaAccessibilityEvent(
-              UIA_SelectionItem_ElementRemovedFromSelectionEventId, item);
-        }
-      }
-    }
-  }
-  selection_events_.clear();
   ignored_changed_nodes_.clear();
 }
 

content/browser/accessibility/browser_accessibility_manager_win.h

@@ -77,7 +77,40 @@ class CONTENT_EXPORT BrowserAccessibilityManagerWin
       const std::vector<ui::AXTreeObserver::Change>& changes) override;
 
  private:
-  void HandleSelectedStateChanged(BrowserAccessibility* node);
+  struct SelectionEvents {
+    std::vector<BrowserAccessibility*> added;
+    std::vector<BrowserAccessibility*> removed;
+    SelectionEvents();
+    ~SelectionEvents();
+  };
+
+  using SelectionEventsMap = std::map<BrowserAccessibility*, SelectionEvents>;
+  using IsSelectedPredicate =
+      base::RepeatingCallback<bool(BrowserAccessibility*)>;
+  using FirePlatformSelectionEventsCallback =
+      base::RepeatingCallback<void(BrowserAccessibility*,
+                                   BrowserAccessibility*,
+                                   const SelectionEvents&)>;
+
+  static bool IsIA2NodeSelected(BrowserAccessibility* node);
+  static bool IsUIANodeSelected(BrowserAccessibility* node);
+
+  void FireIA2SelectionEvents(BrowserAccessibility* container,
+                              BrowserAccessibility* only_selected_child,
+                              const SelectionEvents& changes);
+  void FireUIASelectionEvents(BrowserAccessibility* container,
+                              BrowserAccessibility* only_selected_child,
+                              const SelectionEvents& changes);
+
+  static void HandleSelectedStateChanged(
+      SelectionEventsMap& selection_events_map,
+      BrowserAccessibility* node,
+      bool is_selected);
+
+  static void FinalizeSelectionEvents(
+      SelectionEventsMap& selection_events_map,
+      IsSelectedPredicate is_selected_predicate,
+      FirePlatformSelectionEventsCallback fire_platform_events_callback);
 
   // Give BrowserAccessibilityManager::Create access to our constructor.
   friend class BrowserAccessibilityManager;
@@ -109,13 +142,8 @@ class CONTENT_EXPORT BrowserAccessibilityManagerWin
   // Keep track of selection changes so we can optimize UIA event firing.
   // Pointers are only stored for the duration of |OnAccessibilityEvents|, and
   // the map is cleared in |FinalizeAccessibilityEvents|.
-  struct SelectionEvents {
-    std::vector<BrowserAccessibility*> added;
-    std::vector<BrowserAccessibility*> removed;
-    SelectionEvents();
-    ~SelectionEvents();
-  };
-  std::map<BrowserAccessibility*, SelectionEvents> selection_events_;
+  SelectionEventsMap ia2_selection_events_;
+  SelectionEventsMap uia_selection_events_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserAccessibilityManagerWin);
 };

content/test/data/accessibility/event/aria-checked-changed-expected-uia-win.txt

@@ -2,6 +2,10 @@ AriaProperties changed on role=checkbox, name=checkbox1
 AriaProperties changed on role=checkbox, name=checkbox2
 AriaProperties changed on role=radio, name=radio1
 AriaProperties changed on role=radio, name=radio2
+SelectionItemIsSelected changed on role=radio, name=radio1
+SelectionItemIsSelected changed on role=radio, name=radio2
+SelectionItem_ElementRemovedFromSelection on role=radio, name=radio2
+SelectionItem_ElementSelected on role=radio, name=radio1
 ToggleToggleState changed on role=checkbox, name=checkbox1
 ToggleToggleState changed on role=checkbox, name=checkbox2
 ToggleToggleState changed on role=radio, name=radio1

content/test/data/accessibility/event/aria-combo-box-expand-expected-uia-win.txt

@@ -3,4 +3,5 @@ AriaProperties changed on role=option, name=Apple
 AutomationFocusChanged on role=option, name=Apple
 AutomationFocusChanged on role=option, name=Apple
 ExpandCollapseExpandCollapseState changed on role=combobox
+SelectionItemIsSelected changed on role=option, name=Apple
 SelectionItem_ElementSelected on role=option, name=Apple

content/test/data/accessibility/event/aria-combo-box-expand-expected-uia-win7.txt

@@ -4,4 +4,5 @@ AutomationFocusChanged on role=combobox
 AutomationFocusChanged on role=option, name=Apple
 AutomationFocusChanged on role=option, name=Apple
 ExpandCollapseExpandCollapseState changed on role=combobox
+SelectionItemIsSelected changed on role=option, name=Apple
 SelectionItem_ElementSelected on role=option, name=Apple

content/test/data/accessibility/event/aria-combo-box-next-expected-uia-win.txt

@@ -2,10 +2,14 @@ AriaProperties changed on role=option, name=Apple
 AriaProperties changed on role=option, name=Orange
 AutomationFocusChanged on role=option, name=Orange
 AutomationFocusChanged on role=option, name=Orange
+SelectionItemIsSelected changed on role=option, name=Apple
+SelectionItemIsSelected changed on role=option, name=Orange
 SelectionItem_ElementSelected on role=option, name=Orange
 === Start Continuation ===
 AriaProperties changed on role=option, name=Banana
 AriaProperties changed on role=option, name=Orange
 AutomationFocusChanged on role=option, name=Banana
 AutomationFocusChanged on role=option, name=Banana
+SelectionItemIsSelected changed on role=option, name=Banana
+SelectionItemIsSelected changed on role=option, name=Orange
 SelectionItem_ElementSelected on role=option, name=Banana

content/test/data/accessibility/event/aria-combo-box-next-expected-uia-win7.txt

@@ -3,6 +3,7 @@ AriaProperties changed on role=option, name=Orange
 AutomationFocusChanged on role=option, name=Apple
 AutomationFocusChanged on role=option, name=Orange
 AutomationFocusChanged on role=option, name=Orange
+SelectionItemIsSelected changed on role=option, name=Orange
 SelectionItem_ElementSelected on role=option, name=Orange
 === Start Continuation ===
 AriaProperties changed on role=option, name=Banana
@@ -10,4 +11,5 @@ AriaProperties changed on role=option, name=Orange
 AutomationFocusChanged on role=option, name=Banana
 AutomationFocusChanged on role=option, name=Banana
 AutomationFocusChanged on role=option, name=Orange
+SelectionItemIsSelected changed on role=option, name=Banana
 SelectionItem_ElementSelected on role=option, name=Banana

content/test/data/accessibility/event/aria-selected-changed-expected-uia-win.txt

 AriaProperties changed on role=gridcell, name=Grid1, GridCell1
+SelectionItemIsSelected changed on role=gridcell, name=Grid1, GridCell1
 SelectionItem_ElementRemovedFromSelection on role=gridcell, name=Grid1, GridCell1
 === Start Continuation ===
 AriaProperties changed on role=gridcell, name=Grid2, GridCell2
+SelectionItemIsSelected changed on role=gridcell, name=Grid2, GridCell2
 SelectionItem_ElementAddedToSelection on role=gridcell, name=Grid2, GridCell2
 === Start Continuation ===
 AriaProperties changed on role=gridcell, name=Grid3, GridCell1
+SelectionItemIsSelected changed on role=gridcell, name=Grid3, GridCell1
 SelectionItem_ElementRemovedFromSelection on role=gridcell, name=Grid3, GridCell1
 === Start Continuation ===
 AriaProperties changed on role=gridcell, name=Grid4, GridCell1
 AriaProperties changed on role=gridcell, name=Grid4, GridCell2
+SelectionItemIsSelected changed on role=gridcell, name=Grid4, GridCell1
+SelectionItemIsSelected changed on role=gridcell, name=Grid4, GridCell2
 SelectionItem_ElementRemovedFromSelection on role=gridcell, name=Grid4, GridCell1
 SelectionItem_ElementSelected on role=gridcell, name=Grid4, GridCell2
 === Start Continuation ===
 === Start Continuation ===
 AriaProperties changed on role=combobox
 AriaProperties changed on role=listitem, name=Select2, Option2
+SelectionItemIsSelected changed on role=combobox
+SelectionItemIsSelected changed on role=listitem, name=Select2, Option2
 SelectionItem_ElementSelected on role=listitem, name=Select2, Option2
 ValueValue changed on role=combobox
 === Start Continuation ===
 AriaProperties changed on role=option, name=DivSelect, Option1
 AriaProperties changed on role=option, name=DivSelect, Option2
+SelectionItemIsSelected changed on role=option, name=DivSelect, Option1
+SelectionItemIsSelected changed on role=option, name=DivSelect, Option2
 SelectionItem_ElementSelected on role=option, name=DivSelect, Option2

content/test/data/accessibility/event/focus-listbox-multiselect-expected-uia-win.txt

@@ -2,4 +2,6 @@ AriaProperties changed on role=option, name=b
 AriaProperties changed on role=option, name=c
 AutomationFocusChanged on role=option, name=c
 AutomationFocusChanged on role=option, name=c
+SelectionItemIsSelected changed on role=option, name=b
+SelectionItemIsSelected changed on role=option, name=c
 SelectionItem_ElementSelected on role=option, name=c

content/test/data/accessibility/event/listbox-next-expected-uia-win.txt

@@ -2,4 +2,6 @@ AriaProperties changed on role=option, name=Apple
 AriaProperties changed on role=option, name=Orange
 AutomationFocusChanged on role=option, name=Orange
 AutomationFocusChanged on role=option, name=Orange
+SelectionItemIsSelected changed on role=option, name=Apple
+SelectionItemIsSelected changed on role=option, name=Orange
 SelectionItem_ElementSelected on role=option, name=Orange

content/test/data/accessibility/event/listbox-next-expected-uia-win7.txt

@@ -3,4 +3,5 @@ AriaProperties changed on role=option, name=Orange
 AutomationFocusChanged on role=option, name=Apple
 AutomationFocusChanged on role=option, name=Orange
 AutomationFocusChanged on role=option, name=Orange
+SelectionItemIsSelected changed on role=option, name=Orange
 SelectionItem_ElementSelected on role=option, name=Orange

content/test/data/accessibility/event/menulist-collapse-expected-uia-win.txt

@@ -2,5 +2,6 @@ AutomationFocusChanged on role=combobox
 AutomationFocusChanged on role=combobox
 === Start Continuation ===
 AriaProperties changed on role=combobox
+SelectionItemIsSelected changed on role=combobox
 SelectionItem_ElementRemovedFromSelection on role=combobox
 ValueValue changed on role=combobox

content/test/data/accessibility/event/menulist-collapse-expected-uia-win7.txt

@@ -3,5 +3,6 @@ AutomationFocusChanged on role=combobox
 AutomationFocusChanged on role=combobox
 === Start Continuation ===
 AriaProperties changed on role=combobox
+SelectionItemIsSelected changed on role=combobox
 SelectionItem_ElementRemovedFromSelection on role=combobox
 ValueValue changed on role=combobox

content/test/data/accessibility/event/menulist-collapse-next-expected-uia-win.txt

@@ -3,5 +3,7 @@ AutomationFocusChanged on role=combobox
 === Start Continuation ===
 AriaProperties changed on role=combobox
 AriaProperties changed on role=listitem, name=Orange
+SelectionItemIsSelected changed on role=combobox
+SelectionItemIsSelected changed on role=listitem, name=Orange
 SelectionItem_ElementSelected on role=listitem, name=Orange
 ValueValue changed on role=combobox

content/test/data/accessibility/event/menulist-collapse-next-expected-uia-win7.txt

@@ -5,5 +5,6 @@ AutomationFocusChanged on role=combobox
 AriaProperties changed on role=combobox
 AriaProperties changed on role=listitem, name=Orange
 AutomationFocusChanged on role=combobox
+SelectionItemIsSelected changed on role=listitem, name=Orange
 SelectionItem_ElementSelected on role=listitem, name=Orange
 ValueValue changed on role=combobox

content/test/data/accessibility/event/select-selected-add-remove-expected-uia-win.txt

+SelectionItemIsSelected changed on role=option, name=Option2
 SelectionItem_ElementSelected on role=option, name=Option2
 === Start Continuation ===
+SelectionItemIsSelected changed on role=option, name=Option3
 SelectionItem_ElementAddedToSelection on role=option, name=Option3
 === Start Continuation ===
+SelectionItemIsSelected changed on role=option, name=Option4
 SelectionItem_ElementRemovedFromSelection on role=option, name=Option4
 === Start Continuation ===
+SelectionItemIsSelected changed on role=option, name=Option5
+SelectionItemIsSelected changed on role=option, name=Option6
 SelectionItem_ElementSelected on role=option, name=Option6
 === Start Continuation ===
+SelectionItemIsSelected changed on role=combobox, name=Combo3
+SelectionItemIsSelected changed on role=listitem, name=Option8
 SelectionItem_ElementSelected on role=listitem, name=Option8
 === Start Continuation ===
 Selection_Invalidated on role=listbox, name=Combo4

content/test/data/accessibility/event/select-selected-add-remove.html

 <!--
 @UIA-WIN-DENY:*
 @UIA-WIN-ALLOW:SelectionItem_Element*
+@UIA-WIN-ALLOW:SelectionItemIsSelected*
 @UIA-WIN-ALLOW:Selection_Invalidated*
 -->
 <!DOCTYPE html>

ui/accessibility/ax_role_properties.cc

@@ -403,6 +403,16 @@ bool IsPresentational(const ax::mojom::Role role) {
   }
 }
 
+bool IsRadio(const ax::mojom::Role role) {
+  switch (role) {
+    case ax::mojom::Role::kRadioButton:
+    case ax::mojom::Role::kMenuItemRadio:
+      return true;
+    default:
+      return false;
+  }
+}
+
 bool IsRangeValueSupported(const ax::mojom::Role role) {
   // https://www.w3.org/TR/wai-aria-1.1/#aria-valuenow
   // https://www.w3.org/TR/wai-aria-1.1/#aria-valuetext

ui/accessibility/ax_role_properties.h

@@ -113,6 +113,9 @@ AX_BASE_EXPORT bool IsMenuRelated(const ax::mojom::Role role);
 // API.
 AX_BASE_EXPORT bool IsPresentational(const ax::mojom::Role role);
 
+// Returns true if the provided role belongs to a radio.
+AX_BASE_EXPORT bool IsRadio(const ax::mojom::Role role);
+
 // Returns true if the provided role supports a range-based value, such as a
 // slider.
 AX_BASE_EXPORT bool IsRangeValueSupported(const ax::mojom::Role role);

ui/accessibility/platform/ax_platform_node_win.cc

@@ -7588,6 +7588,10 @@ base::Optional<PROPERTYID> AXPlatformNodeWin::MojoEventToUIAProperty(
     case ax::mojom::Event::kRowCollapsed:
     case ax::mojom::Event::kRowExpanded:
       return UIA_ExpandCollapseExpandCollapseStatePropertyId;
+    case ax::mojom::Event::kSelection:
+    case ax::mojom::Event::kSelectionAdd:
+    case ax::mojom::Event::kSelectionRemove:
+      return UIA_SelectionItemIsSelectedPropertyId;
     default:
       return base::nullopt;
   }