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..4313846081ecd9b2886b18095d45add765f0e6f3 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);
@@ -895,6 +897,22 @@ void DockedWindowLayoutManager::OnOverviewModeEnded() {
   UpdateDockBounds(DockedWindowLayoutManagerObserver::CHILD_CHANGED);
 }
 
+void DockedWindowLayoutManager::OnVirtualKeyboardStateChanged(
+    bool activated,
+    WmWindow* root_window) {
+  if (root_window != dock_container_->GetRootWindow())
+    return;
+
+  keyboard::KeyboardController* const keyboard_controller =
+      keyboard::KeyboardController::GetInstance();
+  if (activated && !keyboard_observer_.IsObserving(keyboard_controller)) {
+    keyboard_observer_.Add(keyboard_controller);
+  } else if (!activated &&
+             keyboard_observer_.IsObserving(keyboard_controller)) {
+    keyboard_observer_.Remove(keyboard_controller);
+  }
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // DockedWindowLayoutManager private implementation:
 
@@ -1337,6 +1355,8 @@ void DockedWindowLayoutManager::OnKeyboardBoundsChanging(
   UpdateDockBounds(DockedWindowLayoutManagerObserver::KEYBOARD_BOUNDS_CHANGING);
 }
 
-void DockedWindowLayoutManager::OnKeyboardClosed() {}
+void DockedWindowLayoutManager::OnKeyboardClosed() {
+  keyboard_observer_.RemoveAll();
+}
 
 }  // namespace ash