(Mac)Views: Widgets focus first View in traversal order if initial focus fails.

ui/views/window/dialog_delegate.cc

 // Copyright (c) 2012 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 "ui/views/window/dialog_delegate.h"
 
 #include <utility>
 
 #include "base/logging.h"
 #include "build/build_config.h"
@@ skipping 145 matching lines @@
   }
   NOTREACHED();
   return base::string16();
 }
 
 bool DialogDelegate::IsDialogButtonEnabled(ui::DialogButton button) const {
   return true;
 }
 
 View* DialogDelegate::GetInitiallyFocusedView() {
+  const DialogClientView* dcv = GetDialogClientView();
+  if (!dcv->GetFocusManager()->keyboard_accessible())

[karandeepb, 2016/12/30 21:16:04]

null-check the focus manager? 

Did you test this on other platforms? keyboard accessibility is off/false on all
platforms except Mac. Hence won't this always return NULL on say Windows? 

We can #ifdef OS_MACOSX this, but I am not sure if this is the correct way to
solve this. (doesn't look generic enough). Another option may be to do something
more sensible in Widget::SetInitialFocus when the initially-focused-view
retrieved can't take focus. For example, what does FocusManager::AdvanceFocus
do, if the focus manager has no focused view?

[Patti Lor, 2017/01/03 03:48:26]

Oops, that's a mistake. I originally had the #ifdefs around this hunk but
removed them for whatever reason. Your suggestion sounds reasonable though -
looks like FocusManager::AdvanceFocus() works when focus is cleared. I've
changed the fix to be in Widget::SetInitialFocus() instead.

[karandeepb, 2017/01/04 00:12:33]

Yeah this seems reasonable to me as well, though owners might have a different
take.

+    return NULL;
+
   // Focus the default button if any.
-  const DialogClientView* dcv = GetDialogClientView();
   int default_button = GetDefaultDialogButton();
   if (default_button == ui::DIALOG_BUTTON_NONE)
     return NULL;
 
   if ((default_button & GetDialogButtons()) == 0) {
     // The default button is a button we don't have.
     NOTREACHED();
     return NULL;
   }
 
@@ skipping 83 matching lines @@
   node_data->role = ui::AX_ROLE_DIALOG;
 }
 
 void DialogDelegateView::ViewHierarchyChanged(
     const ViewHierarchyChangedDetails& details) {
   if (details.is_add && details.child == this && GetWidget())
     NotifyAccessibilityEvent(ui::AX_EVENT_ALERT, true);
 }
 
 }  // namespace views