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

ui/views/accessibility/native_view_accessibility_unittest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/memory/ptr_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "ui/accessibility/ax_node_data.h"
 #include "ui/gfx/geometry/rect_conversions.h"
 #include "ui/views/accessibility/native_view_accessibility.h"
 #include "ui/views/controls/button/button.h"
@@ skipping 52 matching lines @@
  protected:
   views::Widget* widget_;
   TestButton* button_;
   NativeViewAccessibility* button_accessibility_;
   Label* label_;
   NativeViewAccessibility* label_accessibility_;
 };
 
 TEST_F(NativeViewAccessibilityTest, RoleShouldMatch) {
   EXPECT_EQ(ui::AX_ROLE_BUTTON, button_accessibility_->GetData().role);
+#if defined(OS_MACOSX)

[dmazzoni, 2016/11/30 23:12:44]

I'm okay with removing this test or rewriting it to test
something else useful, given this change

[Patti Lor, 2016/12/01 01:12:07]

Will go ahead and do this if it's decided we'll go with a platform independent
approach as per my second comment.

+  // On Mac, the label isn't given a role. Since it's a subview of |button_|
+  // (and the button is focusable), the label is assumed to form part of the
+  // button and not have a role of its own.
+  EXPECT_EQ(ui::AX_ROLE_UNKNOWN, label_accessibility_->GetData().role);
+  // This will happen for all potentially keyboard-focusable Views with
+  // non-keyboard-focusable children, so if we make the button unfocusable, the
+  // label will be allowed to have its own role again.
+  button_->SetFocusBehavior(View::FocusBehavior::NEVER);
+#endif
   EXPECT_EQ(ui::AX_ROLE_STATIC_TEXT, label_accessibility_->GetData().role);
 }
 
 TEST_F(NativeViewAccessibilityTest, BoundsShouldMatch) {
   gfx::Rect bounds = gfx::ToEnclosingRect(
       button_accessibility_->GetData().location);
   bounds.Offset(button_accessibility_->GetGlobalCoordinateOffset());
   EXPECT_EQ(button_->GetBoundsInScreen(), bounds);
 }
 
@@ skipping 55 matching lines @@
   // WidgetObserver. Note that TestNativeViewAccessibility is a subclass
   // defined above that destroys itself when its parent widget is destroyed.
   TestNativeViewAccessibility* child_accessible =
       new TestNativeViewAccessibility(child_widget->GetRootView());
   child_accessible->SetParentWidget(parent_widget.get());
   parent_widget.reset();
 }
 
 }  // namespace test
 }  // namespace views