Move the concept of Activation to the Shell.

ui/views/widget/native_widget_aura.cc

Index: ui/views/widget/native_widget_aura.cc
===================================================================
--- ui/views/widget/native_widget_aura.cc	(revision 114022)
+++ ui/views/widget/native_widget_aura.cc	(working copy)
@@ -6,13 +6,14 @@
 
 #include "base/bind.h"
 #include "base/string_util.h"
+#include "ui/aura/client/activation_client.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/client/drag_drop_client.h"
 #include "ui/aura/client/shadow_types.h"
 #include "ui/aura/event.h"
 #include "ui/aura/root_window.h"
-#include "ui/aura/root_window_observer.h"
 #include "ui/aura/window.h"
+#include "ui/aura/window_observer.h"
 #include "ui/aura/window_types.h"
 #include "ui/base/dragdrop/os_exchange_data.h"
 #include "ui/base/ui_base_types.h"
@@ -76,20 +77,23 @@
 
 // Used when SetInactiveRenderingDisabled() is invoked to track when active
 // status changes in such a way that we should enable inactive rendering.
-class NativeWidgetAura::RootWindowObserverImpl
-    : public aura::RootWindowObserver {
+class NativeWidgetAura::ActiveWindowObserver : public aura::WindowObserver {
  public:
-  explicit RootWindowObserverImpl(NativeWidgetAura* host)
-      : host_(host) {
+  explicit ActiveWindowObserver(NativeWidgetAura* host) : host_(host) {
     aura::RootWindow::GetInstance()->AddObserver(this);
   }
-
-  virtual ~RootWindowObserverImpl() {
+  virtual ~ActiveWindowObserver() {
     aura::RootWindow::GetInstance()->RemoveObserver(this);
   }
 
-  // RootWindowObserver overrides:
-  virtual void OnActiveWindowChanged(aura::Window* active) OVERRIDE {
+  // Overridden from aura::WindowObserver:
+  virtual void OnWindowPropertyChanged(aura::Window* window,
+                                       const char* key,
+                                       void* old) OVERRIDE {
+    if (key != aura::kRootWindowActiveWindow)
+      return;
+    aura::Window* active =
+        aura::ActivationClient::GetActivationClient()->GetActiveWindow();
     if (!active || (active != host_->window_ &&
                     active->transient_parent() != host_->window_)) {
       host_->delegate_->EnableInactiveRendering();
@@ -99,7 +103,7 @@
  private:
   NativeWidgetAura* host_;
 
-  DISALLOW_COPY_AND_ASSIGN(RootWindowObserverImpl);
+  DISALLOW_COPY_AND_ASSIGN(ActiveWindowObserver);
 };
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -181,6 +185,8 @@
         static_cast<aura::WindowDragDropDelegate*>(this));
   }
 
+  aura::ActivationDelegate::SetActivationDelegate(window_, this);
+
   if (window_type == Widget::InitParams::TYPE_MENU ||
       window_type == Widget::InitParams::TYPE_TOOLTIP)
     window_->SetIntProperty(aura::kShadowTypeKey,
@@ -425,7 +431,7 @@
   window_->Show();
   if (can_activate_ && (state != ui::SHOW_STATE_INACTIVE ||
                         !GetWidget()->SetInitialFocus())) {
-    window_->Activate();
+    Activate();
   }
 }
 
@@ -434,15 +440,16 @@
 }
 
 void NativeWidgetAura::Activate() {
-  window_->Activate();
+  aura::ActivationClient::GetActivationClient()->ActivateWindow(window_);
 }
 
 void NativeWidgetAura::Deactivate() {
-  window_->Deactivate();
+  aura::ActivationClient::GetActivationClient()->DeactivateWindow(window_);
 }
 
 bool NativeWidgetAura::IsActive() const {
-  return aura::RootWindow::GetInstance()->active_window() == window_;
+  return aura::ActivationClient::GetActivationClient()->GetActiveWindow() ==
+      window_;
 }
 
 void NativeWidgetAura::SetAlwaysOnTop(bool on_top) {
@@ -532,9 +539,9 @@
 
 void NativeWidgetAura::SetInactiveRenderingDisabled(bool value) {
   if (!value)
-    root_window_observer_.reset();
+    active_window_observer_.reset();
   else
-    root_window_observer_.reset(new RootWindowObserverImpl(this));
+    active_window_observer_.reset(new ActiveWindowObserver(this));
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -629,22 +636,6 @@
   return true;
 }
 
-bool NativeWidgetAura::ShouldActivate(aura::Event* event) {
-  return can_activate_;
-}
-
-void NativeWidgetAura::OnActivated() {
-  delegate_->OnNativeWidgetActivationChanged(true);
-  if (IsVisible() && GetWidget()->non_client_view())
-    GetWidget()->non_client_view()->SchedulePaint();
-}
-
-void NativeWidgetAura::OnLostActive() {
-  delegate_->OnNativeWidgetActivationChanged(false);
-  if (IsVisible() && GetWidget()->non_client_view())
-    GetWidget()->non_client_view()->SchedulePaint();
-}
-
 void NativeWidgetAura::OnCaptureLost() {
   delegate_->OnMouseCaptureLost();
 }
@@ -673,6 +664,28 @@
   delegate_->OnNativeWidgetVisibilityChanged(visible);
 }
 
+////////////////////////////////////////////////////////////////////////////////
+// NativeWidgetAura, aura::ActivationDelegate implementation:
+
+bool NativeWidgetAura::ShouldActivate(aura::Event* event) {
+  return can_activate_;
+}
+
+void NativeWidgetAura::OnActivated() {
+  delegate_->OnNativeWidgetActivationChanged(true);
+  if (IsVisible() && GetWidget()->non_client_view())
+    GetWidget()->non_client_view()->SchedulePaint();
+}
+
+void NativeWidgetAura::OnLostActive() {
+  delegate_->OnNativeWidgetActivationChanged(false);
+  if (IsVisible() && GetWidget()->non_client_view())
+    GetWidget()->non_client_view()->SchedulePaint();
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// NativeWidgetAura, aura::WindowDragDropDelegate implementation:
+
 void NativeWidgetAura::OnDragEntered(const aura::DropTargetEvent& event) {
   DCHECK(drop_helper_.get() != NULL);
   drop_helper_->OnDragOver(event.data(), event.location(),