[Not For Review] Handle a view that that isn't a part of Widget tree focusManager handles

ui/views/focus/focus_manager.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/focus/focus_manager.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "base/auto_reset.h"
@@ skipping 283 matching lines @@
   keyboard_accessible_ = keyboard_accessible;
   // Disabling keyboard accessibility may cause the focused view to become not
   // focusable. Hence advance focus if necessary.
   AdvanceFocusIfNecessary();
 }
 
 void FocusManager::SetFocusedViewWithReason(
     View* view, FocusChangeReason reason) {
   if (focused_view_ == view)
     return;
-  // TODO(oshima|achuith): This is to diagnose crbug.com/687232.
-  // Change this to DCHECK once it's resolved.
-  CHECK(!view || ContainsView(view));
 
 #if !defined(OS_MACOSX)
   // TODO(warx): There are some AccessiblePaneViewTest failed on macosx.
   // crbug.com/650859. Remove !defined(OS_MACOSX) once that is fixed.
   //
   // If the widget isn't active store the focused view and then attempt to
   // activate the widget. If activation succeeds |view| will be focused.
   // If activation fails |view| will be focused the next time the widget is
   // made active.
   if (view && !widget_->IsActive()) {
     SetStoredFocusView(view);
     widget_->Activate();
     return;
   }
 #endif
 
   // Update the reason for the focus change (since this is checked by
   // some listeners), then notify all listeners.
   focus_change_reason_ = reason;
   for (FocusChangeListener& observer : focus_change_listeners_)
     observer.OnWillChangeFocus(focused_view_, view);
 
   View* old_focused_view = focused_view_;
-  focused_view_ = view;
+
+  bool focused_view_on_other_widget = view && !ContainsView(view);
+  if (focused_view_on_other_widget) {
+    focused_view_ = nullptr;
+  } else {
+    focused_view_ = view;
+  }
   if (old_focused_view)
     old_focused_view->Blur();
   // Also make |focused_view_| the stored focus view. This way the stored focus
   // view is remembered if focus changes are requested prior to a show or while
   // hidden.
-  SetStoredFocusView(focused_view_);
-  if (focused_view_)
+  if (!focused_view_on_other_widget) {
+    SetStoredFocusView(focused_view_);
+  }
+  if (focused_view_) {
     focused_view_->Focus();
+  } else if (view) {
+    view->RequestFocus();
+  }
 
   for (FocusChangeListener& observer : focus_change_listeners_)
     observer.OnDidChangeFocus(old_focused_view, focused_view_);
 }
 
 void FocusManager::ClearFocus() {
   // SetFocusedView(NULL) is going to clear out the stored view to. We need to
   // persist it in this case.
   views::View* focused_view = GetStoredFocusView();
   SetFocusedView(NULL);
@@ skipping 210 matching lines @@
 // |keyboard_accessible_| is only used on Mac.
 #if defined(OS_MACOSX)
   return keyboard_accessible_ ? view->IsAccessibilityFocusable()
                               : view->IsFocusable();
 #else
   return view->IsAccessibilityFocusable();
 #endif
 }
 
 }  // namespace views