ash: Move VirtualKeyboardStateObserver functionality to ShellObserver

ash/test/test_shell_delegate.h

Index: ash/test/test_shell_delegate.h
diff --git a/ash/test/test_shell_delegate.h b/ash/test/test_shell_delegate.h
index fb0d555878d399c32f1948680e61c282e3f5c543..bc9b92d49916b54271cf790463f2d8956f49bf4b 100644
--- a/ash/test/test_shell_delegate.h
+++ b/ash/test/test_shell_delegate.h
@@ -12,7 +12,6 @@
 #include "ash/common/shell_delegate.h"
 #include "ash/test/test_session_state_delegate.h"
 #include "base/macros.h"
-#include "base/observer_list.h"
 
 namespace app_list {
 class AppListPresenterDelegateFactory;
@@ -46,11 +45,6 @@ class TestShellDelegate : public ShellDelegate {
   void PreShutdown() override;
   void Exit() override;
   keyboard::KeyboardUI* CreateKeyboardUI() override;
-  void VirtualKeyboardActivated(bool activated) override;
-  void AddVirtualKeyboardStateObserver(
-      VirtualKeyboardStateObserver* observer) override;
-  void RemoveVirtualKeyboardStateObserver(
-      VirtualKeyboardStateObserver* observer) override;
   void OpenUrl(const GURL& url) override;
   app_list::AppListPresenter* GetAppListPresenter() override;
   ShelfDelegate* CreateShelfDelegate(ShelfModel* model) override;
@@ -88,9 +82,6 @@ class TestShellDelegate : public ShellDelegate {
       app_list_presenter_delegate_factory_;
   std::unique_ptr<app_list::AppListPresenterImpl> app_list_presenter_;
 
-  base::ObserverList<VirtualKeyboardStateObserver>
-      keyboard_state_observer_list_;
-
   DISALLOW_COPY_AND_ASSIGN(TestShellDelegate);
 };