Automatically fire AX events on Win based on tree changes

content/browser/accessibility/browser_accessibility_manager.cc

Index: content/browser/accessibility/browser_accessibility_manager.cc
diff --git a/content/browser/accessibility/browser_accessibility_manager.cc b/content/browser/accessibility/browser_accessibility_manager.cc
index 30099107b3367fd38b4c252f607dfce51932bd38..87ee8196c4134ac9c6214a0ca241c31032dd5ea2 100644
--- a/content/browser/accessibility/browser_accessibility_manager.cc
+++ b/content/browser/accessibility/browser_accessibility_manager.cc
@@ -434,9 +434,14 @@ void BrowserAccessibilityManager::OnAccessibilityEvents(
 
     ui::AXEvent event_type = detail.event_type;
 
-#if defined(OS_MACOSX)
-    if (event_type != ui::AX_EVENT_HOVER)
+// On Mac and Windows, nearly all events are now fired implicitly,
+// so we should ignore most events from the renderer.
+#if defined(OS_MACOSX) || defined(OS_WIN)
+    if (event_type != ui::AX_EVENT_HOVER &&
+        event_type != ui::AX_EVENT_LOCATION_CHANGED &&
+        event_type != ui::AX_EVENT_SCROLLED_TO_ANCHOR) {
       continue;
+    }
 #endif  // !defined(OS_MACOSX)
 
     if (event_type == ui::AX_EVENT_FOCUS ||