Relanding focus manager refactoring

views/focus/focus_manager_win.cc

+// Copyright (c) 2006-2009 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 "views/focus/focus_manager.h"
+
+#include "views/view.h"
+#include "views/widget/widget_win.h"
+
+namespace views {
+
+void FocusManager::ClearNativeFocus() {
+  // Keep the top root window focused so we get keyboard events.
+  ::SetFocus(widget_->GetNativeView());
+}
+
+void FocusManager::FocusNativeView(gfx::NativeView native_view) {
+  // Only reset focus if hwnd is not already focused.
+  if (native_view && ::GetFocus() != native_view)
+    ::SetFocus(native_view);
+}
+
+// static
+FocusManager* FocusManager::GetFocusManagerForNativeView(
+    gfx::NativeView native_view) {
+  HWND root = ::GetAncestor(native_view, GA_ROOT);
+  if (!root)
+    return NULL;
+  WidgetWin* widget = WidgetWin::GetWidget(root);
+  return widget ? widget->GetFocusManager() : NULL;
+}
+
+}  // namespace views
+