Fire UIA/MSAA menu start/end events when menu is shown/hidden

Menu events should fire when a menu is made visible or hidden, whether
or not the menu or something within it gets
focused, because some authors simply show the menu at first, and
only move focus if the user arrows into it. If the menupopupstart
doesn't fire when the menu first appears, then the screen reader
does not know to change to focus mode (virtual cursor off), and
the web page will not receive down arrow keys.

This also matches the behavior of Firefox for menupopupstart.

See the two bugs listed. One contains a general simplified test case
and the other describes how to reproduce the issue with Gmail.

Bug: 98981, 964546
Change-Id: I975513ba73f3b23e884a7f1b38e6b5b161028d17
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1637057Reviewed-by: Ian Prest <iapres@microsoft.com>
Commit-Queue: Aaron Leventhal <aleventhal@chromium.org>
Cr-Commit-Position: refs/heads/master@{#666478}

content/browser/accessibility/accessibility_tree_formatter_utils_win.cc

@@ -191,6 +191,8 @@ CONTENT_EXPORT base::string16 AccessibilityEventToString(int32_t event) {
       QUOTE(EVENT_OBJECT_DRAGLEAVE),
       QUOTE(EVENT_OBJECT_DRAGDROPPED),
       QUOTE(EVENT_SYSTEM_ALERT),
+      QUOTE(EVENT_SYSTEM_MENUPOPUPSTART),
+      QUOTE(EVENT_SYSTEM_MENUPOPUPEND),
       QUOTE(EVENT_SYSTEM_SCROLLINGSTART),
       QUOTE(EVENT_SYSTEM_SCROLLINGEND),
       QUOTE(IA2_EVENT_ACTION_CHANGED),

content/browser/accessibility/browser_accessibility_manager_win.cc

@@ -82,6 +82,10 @@ void BrowserAccessibilityManagerWin::OnSubtreeWillBeDeleted(ui::AXTree* tree,
   BrowserAccessibility* obj = GetFromAXNode(node);
   FireWinAccessibilityEvent(EVENT_OBJECT_HIDE, obj);
   FireUiaStructureChangedEvent(StructureChangeType_ChildRemoved, obj);
+  if (obj && obj->GetRole() == ax::mojom::Role::kMenu) {
+    FireWinAccessibilityEvent(EVENT_SYSTEM_MENUPOPUPEND, obj);
+    FireUiaAccessibilityEvent(UIA_MenuClosedEventId, obj);
+  }
 }
 
 void BrowserAccessibilityManagerWin::UserIsReloading() {
@@ -99,9 +103,6 @@ void BrowserAccessibilityManagerWin::FireFocusEvent(
   BrowserAccessibilityManager::FireFocusEvent(node);
   DCHECK(node);
 
-  if (node->GetRole() == ax::mojom::Role::kMenu)
-    FireUiaAccessibilityEvent(UIA_MenuOpenedEventId, node);
-
   FireWinAccessibilityEvent(EVENT_OBJECT_FOCUS, node);
   FireUiaAccessibilityEvent(UIA_AutomationFocusChangedEventId, node);
 }
@@ -347,6 +348,10 @@ void BrowserAccessibilityManagerWin::FireGeneratedEvent(
     case ui::AXEventGenerator::Event::SUBTREE_CREATED:
       FireWinAccessibilityEvent(EVENT_OBJECT_SHOW, node);
       FireUiaStructureChangedEvent(StructureChangeType_ChildAdded, node);
+      if (node->GetRole() == ax::mojom::Role::kMenu) {
+        FireWinAccessibilityEvent(EVENT_SYSTEM_MENUPOPUPSTART, node);
+        FireUiaAccessibilityEvent(UIA_MenuOpenedEventId, node);
+      }
       break;
     case ui::AXEventGenerator::Event::VALUE_CHANGED:
       FireWinAccessibilityEvent(EVENT_OBJECT_VALUECHANGE, node);
@@ -393,9 +398,6 @@ void BrowserAccessibilityManagerWin::FireGeneratedEvent(
 void BrowserAccessibilityManagerWin::OnFocusLost(BrowserAccessibility* node) {
   BrowserAccessibilityManager::OnFocusLost(node);
   DCHECK(node);
-
-  if (node->GetRole() == ax::mojom::Role::kMenu)
-    FireUiaAccessibilityEvent(UIA_MenuClosedEventId, node);
 }
 
 void BrowserAccessibilityManagerWin::FireWinAccessibilityEvent(

content/test/data/accessibility/event/menu-opened-closed-expected-uia-win.txt

 MenuOpened on role=menu, name=menu
 === Start Continuation ===
-MenuClosed on role=menu, name=menu
-MenuOpened on role=menu, name=submenu1
+MenuOpened on role=menu
 === Start Continuation ===
-MenuClosed on role=menu, name=submenu1
+MenuClosed 
+MenuClosed on role=menu
 === Start Continuation ===
-MenuOpened on role=menu, name=submenu2
-=== Start Continuation ===
-MenuClosed on role=menu, name=submenu2
+MenuClosed 
+MenuClosed on role=menu, name=menu
\ No newline at end of file

content/test/data/accessibility/event/menu-opened-closed-expected-win.txt

+EVENT_SYSTEM_MENUPOPUPSTART on <div#menu> role=ROLE_SYSTEM_MENUPOPUP name="menu" IA2_STATE_VERTICAL SetSize=2
+=== Start Continuation ===
+EVENT_SYSTEM_MENUPOPUPSTART on <div#submenu> role=ROLE_SYSTEM_MENUPOPUP IA2_STATE_VERTICAL SetSize=1
+=== Start Continuation ===
+EVENT_SYSTEM_MENUPOPUPEND on <div#submenu> role=ROLE_SYSTEM_MENUPOPUP IA2_STATE_VERTICAL
+=== Start Continuation ===
+EVENT_SYSTEM_MENUPOPUPEND on <div#menu> role=ROLE_SYSTEM_MENUPOPUP name="menu" IA2_STATE_VERTICAL

content/test/data/accessibility/event/menu-opened-closed.html

 <!--
-@WIN-DENY:EVENT_OBJECT_FOCUS*
-@UIA-WIN-DENY:AutomationFocusChanged*
+@WIN-DENY:EVENT_OBJECT_REORDER*
+@WIN-DENY:EVENT_OBJECT_SHOW*
+@WIN-DENY:EVENT_OBJECT_HIDE*
+@WIN-DENY:IA2_EVENT_TEXT_INSERTED*
+@WIN-DENY:IA2_EVENT_TEXT_REMOVED*
+@UIA-WIN-DENY:*StructureChanged*
+@UIA-WIN_DENY:AutomationFocusChanged*
 -->
 <!DOCTYPE html>
-<div tabindex="1" id="menu" aria-label="menu" role="menu">
-  <div tabindex="2" id="submenu1" aria-label="submenu1" role="menu"></div>
-  <div tabindex="3" id="submenu2" aria-label="submenu2" role="menu">
-    <div tabindex="4" id="option" aria-label="option" role="menuitem"></div>
+<div id="menu" aria-label="menu" role="menu" style="display: none">
+  <div tabindex="2" id="menuitem1" aria-label="submenu1" role="menuitem"></div>
+  <div tabindex="3" id="menuitem2" aria-label="submenu2" role="menuitem">
+    <div id="submenu" role="menu" style="display:none">
+      <div tabindex="4" id="menuitem2.1" aria-label="option" role="menuitem"></div>
+    </div>
   </div>
 </div>
 <script>
   const go_passes = [
-    () => document.getElementById('menu').focus(),
-    () => document.getElementById('submenu1').focus(),
-    () => document.getElementById('submenu1').blur(),
-    () => document.getElementById('submenu2').focus(),
-    () => document.getElementById('option').focus(),
+    () => document.getElementById('menu').style.display = 'block',
+    () => document.getElementById('submenu').style.display = 'block',
+    () => document.getElementById('submenu').style.display = 'none',
+    () => document.getElementById('menu').style.display = 'none',
   ];
 
   var current_pass = 0;