a11y: Exclude children of nested keyboard accessible controls from a11y tree.

ui/views/accessibility/native_view_accessibility.cc

Index: ui/views/accessibility/native_view_accessibility.cc
diff --git a/ui/views/accessibility/native_view_accessibility.cc b/ui/views/accessibility/native_view_accessibility.cc
index 7c960348478b020d7b0bfeed5adf0f50f45e5d70..47bb4cb4c5fa32a5bab210577c35e0b80bdc8d19 100644
--- a/ui/views/accessibility/native_view_accessibility.cc
+++ b/ui/views/accessibility/native_view_accessibility.cc
@@ -13,6 +13,24 @@
 
 namespace views {
 
+#if defined(OS_MACOSX)
+namespace {
+
+bool IsAccessibilityFocusableWhenEnabled(View* view) {
+  return view->focus_behavior() != View::FocusBehavior::NEVER &&
+         view->IsDrawn();
+}
+
+bool ViewHasFocusableAncestor(View* parent) {

[tapted, 2016/11/29 03:12:49]

nit: parent -> view (since it's not the parent that's passed in)

[Patti Lor, 2016/11/29 23:26:18]

Done.

+  while ((parent = parent->parent())) {
+    if (IsAccessibilityFocusableWhenEnabled(parent))
+      return true;
+  }
+  return false;
+}
+}

[tapted, 2016/11/29 03:12:49]

nit:  // namespace  (and and a blank line before, if clang-format lets you)

[Patti Lor, 2016/11/29 23:26:18]

Thanks - it seems to not let you if you've only got 1 method inside the anon
namespace, but two or more is fine.

+#endif
+
 #if !defined(PLATFORM_HAS_NATIVE_VIEW_ACCESSIBILITY_IMPL)
 // static
 NativeViewAccessibility* NativeViewAccessibility::Create(View* view) {
@@ -80,13 +98,22 @@ const ui::AXNodeData& NativeViewAccessibility::GetData() {
                            base::UTF16ToUTF8(description));
 
   if (view_->IsAccessibilityFocusable())
-    data_.state |= (1 << ui::AX_STATE_FOCUSABLE);
+    data_.AddStateFlag(ui::AX_STATE_FOCUSABLE);
 
   if (!view_->enabled())
-    data_.state |= (1 << ui::AX_STATE_DISABLED);
+    data_.AddStateFlag(ui::AX_STATE_DISABLED);
 
   if (!view_->visible())
-    data_.state |= (1 << ui::AX_STATE_INVISIBLE);
+    data_.AddStateFlag(ui::AX_STATE_INVISIBLE);
+
+#if defined(OS_MACOSX)
+  // Make sure this element is ignored if there's a focusable parent. All
+  // keyboard focusable elements should be leaf nodes in the accessibility tree.
+  // Exceptions to this rule will themselves be accessibility focusable.
+  if (!IsAccessibilityFocusableWhenEnabled(view_) &&
+      ViewHasFocusableAncestor(view_))
+    data_.role = ui::AX_ROLE_UNKNOWN;
+#endif
 
   return data_;
 }
@@ -140,7 +167,7 @@ gfx::NativeViewAccessible NativeViewAccessibility::GetParent() {
 }
 
 gfx::Vector2d NativeViewAccessibility::GetGlobalCoordinateOffset() {
-  return gfx::Vector2d(0, 0);  // location is already in screen coordinates.
+  return gfx::Vector2d(0, 0);  // Location is already in screen coordinates.
 }
 
 gfx::NativeViewAccessible NativeViewAccessibility::HitTestSync(int x, int y) {
@@ -163,9 +190,9 @@ gfx::NativeViewAccessible NativeViewAccessibility::HitTestSync(int x, int y) {
   if (!view_->HitTestPoint(point))
     return nullptr;
 
-  // Check if the point is within any of the immediate children of this
-  // view. We don't have to search further because AXPlatformNode will
-  // do a recursive hit test if we return anything other than |this| or NULL.
+  // Check if the point is within any of the immediate children of this view. We
+  // don't have to search further because AXPlatformNodeWin will do a recursive
+  // hit test if we return anything other than GetNativeObject() or nullptr.
   for (int i = view_->child_count() - 1; i >= 0; --i) {
     View* child_view = view_->child_at(i);
     if (!child_view->visible())