Rename StackingClient -> WindowTreeClient

Remove SetDefaultParentForRootWindow from Window, and replace with new utility function ParentWindowForContext in window_tree_client.h
This is part of my current campaign to slim down the aura Window types. I will eventually move WindowTreeClient to a new ui/wm component that I plan to create.

R=erg@chromium.org
http://crbug.com/308844

Review URL: https://codereview.chromium.org/36473003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@230501 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 56 insertions, 0 deletions

diff --git a/ui/aura/client/window_tree_client.h b/ui/aura/client/window_tree_client.h
new file mode 100644
index 0000000..59cb132
--- /dev/null
+++ b/ui/aura/client/window_tree_client.h
@@ -0,0 +1,56 @@
+// Copyright (c) 2013 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.
+
+#ifndef UI_AURA_CLIENT_WINDOW_TREE_CLIENT_H_
+#define UI_AURA_CLIENT_WINDOW_TREE_CLIENT_H_
+
+#include "ui/aura/aura_export.h"
+
+namespace gfx {
+class Rect;
+}
+
+namespace aura {
+class Window;
+namespace client {
+
+// Implementations of this object are used to help locate a default parent for
+// NULL-parented Windows.
+class AURA_EXPORT WindowTreeClient {
+ public:
+  virtual ~WindowTreeClient() {}
+
+  // Called by the Window when it looks for a default parent. Returns the
+  // window that |window| should be added to instead. |context| provides a
+  // Window (generally a RootWindow) that can be used to determine which
+  // desktop type the default parent should be chosen from.  NOTE: this may
+  // have side effects. It should only be used when |window| is going to be
+  // immediately added.
+  //
+  // TODO(erg): Remove |context|, and maybe after oshima's patch lands,
+  // |bounds|.
+  virtual Window* GetDefaultParent(
+      Window* context,
+      Window* window,
+      const gfx::Rect& bounds) = 0;
+};
+
+// Set/Get a window tree client for the RootWindow containing |window|. |window|
+// must not be NULL.
+AURA_EXPORT void SetWindowTreeClient(Window* window,
+                                     WindowTreeClient* window_tree_client);
+WindowTreeClient* GetWindowTreeClient(Window* window);
+
+// Adds |window| to an appropriate parent by consulting an implementation of
+// WindowTreeClient attached at the root Window containing |context|. The final
+// location may be a window hierarchy other than the one supplied via
+// |context|, which must not be NULL. |screen_bounds| may be empty.
+AURA_EXPORT void ParentWindowWithContext(Window* window,
+                                         Window* context,
+                                         const gfx::Rect& screen_bounds);
+
+}  // namespace client
+}  // namespace aura
+
+#endif  // UI_AURA_CLIENT_WINDOW_TREE_CLIENT_H_