ash: Start/stop observing KeyboardController via ShellObserver

ash/common/wm/dock/docked_window_layout_manager.cc

Index: ash/common/wm/dock/docked_window_layout_manager.cc
diff --git a/ash/common/wm/dock/docked_window_layout_manager.cc b/ash/common/wm/dock/docked_window_layout_manager.cc
index d004da93c359f6c4110ba479906d899cc684e1af..273ee2e5747410463170ac1169727c9be1b0e7e8 100644
--- a/ash/common/wm/dock/docked_window_layout_manager.cc
+++ b/ash/common/wm/dock/docked_window_layout_manager.cc
@@ -30,6 +30,7 @@
 #include "ui/compositor/scoped_layer_animation_settings.h"
 #include "ui/display/display.h"
 #include "ui/display/screen.h"
+#include "ui/keyboard/keyboard_controller.h"
 #include "ui/views/background.h"
 #include "ui/wm/core/coordinate_conversion.h"
 #include "ui/wm/core/window_animations.h"
@@ -381,7 +382,8 @@ DockedWindowLayoutManager::DockedWindowLayoutManager(WmWindow* dock_container)
       event_source_(DOCKED_ACTION_SOURCE_UNKNOWN),
       last_active_window_(nullptr),
       last_action_time_(base::Time::Now()),
-      background_widget_(nullptr) {
+      background_widget_(nullptr),
+      keyboard_observer_(this) {
   DCHECK(dock_container);
   Shell::GetInstance()->AddShellObserver(this);
   Shell::GetInstance()->activation_client()->AddObserver(this);
@@ -629,6 +631,18 @@ void DockedWindowLayoutManager::OnShelfBoundsChanged() {
   UpdateDockBounds(DockedWindowLayoutManagerObserver::DISPLAY_INSETS_CHANGED);
 }
 
+void DockedWindowLayoutManager::StartObservingKeyboard(
+    keyboard::KeyboardController* keyboard_controller) {
+  DCHECK(!keyboard_observer_.IsObservingSources());
+  keyboard_observer_.Add(keyboard_controller);
+}
+
+void DockedWindowLayoutManager::StopObservingKeyboard(
+    keyboard::KeyboardController* keyboard_controller) {
+  if (keyboard_observer_.IsObserving(keyboard_controller))
+    keyboard_observer_.Remove(keyboard_controller);
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // DockedWindowLayoutManager, aura::LayoutManager implementation:
 void DockedWindowLayoutManager::OnWindowResized() {
@@ -1337,6 +1351,8 @@ void DockedWindowLayoutManager::OnKeyboardBoundsChanging(
   UpdateDockBounds(DockedWindowLayoutManagerObserver::KEYBOARD_BOUNDS_CHANGING);
 }
 
-void DockedWindowLayoutManager::OnKeyboardClosed() {}
+void DockedWindowLayoutManager::OnKeyboardClosed() {
+  keyboard_observer_.RemoveAll();
+}
 
 }  // namespace ash