Reland of Improves focus/activation for aura-mus and DesktopNativeWidgetAura

ui/aura/mus/focus_synchronizer.cc

Index: ui/aura/mus/focus_synchronizer.cc
diff --git a/ui/aura/mus/focus_synchronizer.cc b/ui/aura/mus/focus_synchronizer.cc
new file mode 100644
index 0000000000000000000000000000000000000000..8f69615ed114e661e44532fe83df35feb6538795
--- /dev/null
+++ b/ui/aura/mus/focus_synchronizer.cc
@@ -0,0 +1,98 @@
+// Copyright 2016 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/aura/mus/focus_synchronizer.h"
+
+#include "base/auto_reset.h"
+#include "services/ui/public/interfaces/window_tree.mojom.h"
+#include "ui/aura/client/focus_client.h"
+#include "ui/aura/env.h"
+#include "ui/aura/mus/focus_synchronizer_delegate.h"
+#include "ui/aura/mus/window_mus.h"
+#include "ui/aura/window.h"
+
+namespace aura {
+
+FocusSynchronizer::FocusSynchronizer(FocusSynchronizerDelegate* delegate,
+                                     ui::mojom::WindowTree* window_tree)
+    : delegate_(delegate), window_tree_(window_tree) {
+  Env::GetInstance()->AddObserver(this);
+}
+
+FocusSynchronizer::~FocusSynchronizer() {
+  SetActiveFocusClient(nullptr);
+  Env::GetInstance()->RemoveObserver(this);
+}
+
+void FocusSynchronizer::SetFocusFromServer(WindowMus* window) {
+  if (focused_window_ == window)
+    return;
+
+  DCHECK(!setting_focus_);
+  base::AutoReset<bool> focus_reset(&setting_focus_, true);
+  base::AutoReset<WindowMus*> window_setting_focus_to_reset(
+      &window_setting_focus_to_, window);
+  Env* env = aura::Env::GetInstance();
+  if (window) {
+    Window* root = window->GetWindow()->GetRootWindow();
+    if (env->active_focus_client_root() != root)
+      env->SetActiveFocusClient(aura::client::GetFocusClient(root), root);
+    window->GetWindow()->Focus();
+  } else if (env->active_focus_client()) {
+    env->active_focus_client()->FocusWindow(nullptr);
+  }
+}
+
+void FocusSynchronizer::OnFocusedWindowDestroyed() {
+  focused_window_ = nullptr;
+}
+
+void FocusSynchronizer::SetActiveFocusClient(
+    client::FocusClient* focus_client) {
+  if (focus_client == active_focus_client_)
+    return;
+
+  if (active_focus_client_)
+    active_focus_client_->RemoveObserver(this);
+  active_focus_client_ = focus_client;
+  if (active_focus_client_)
+    active_focus_client_->AddObserver(this);
+}
+
+void FocusSynchronizer::SetFocusedWindow(WindowMus* window) {
+  const uint32_t change_id = delegate_->CreateChangeIdForFocus(focused_window_);
+  focused_window_ = window;
+  window_tree_->SetFocus(change_id,
+                         window ? window->server_id() : kInvalidServerId);
+}
+
+void FocusSynchronizer::OnWindowFocused(Window* gained_focus,
+                                        Window* lost_focus) {
+  WindowMus* gained_focus_mus = WindowMus::Get(gained_focus);
+  if (setting_focus_ && gained_focus_mus == window_setting_focus_to_) {
+    focused_window_ = gained_focus_mus;
+    return;
+  }
+  SetFocusedWindow(gained_focus_mus);
+}
+
+void FocusSynchronizer::OnWindowInitialized(Window* window) {}
+
+void FocusSynchronizer::OnActiveFocusClientChanged(
+    client::FocusClient* focus_client,
+    Window* window) {
+  SetActiveFocusClient(focus_client);
+  if (setting_focus_)
+    return;
+
+  if (focus_client) {
+    Window* focused_window = focus_client->GetFocusedWindow();
+    SetFocusedWindow(focused_window ? WindowMus::Get(focused_window)
+                                    : WindowMus::Get(window));
+  } else {
+    SetFocusedWindow(nullptr);
+  }
+}
+
+}  // namespace aura