Move DefaultActivationClient to wm/core

ui/wm/core/shadow_controller_unittest.cc

Index: ui/wm/core/shadow_controller_unittest.cc
diff --git a/ui/wm/core/shadow_controller_unittest.cc b/ui/wm/core/shadow_controller_unittest.cc
index 60d571e0c7042a30c553800d79437bcc6a177179..d82d015f1a0badb133c8414215b6a138b72bb496 100644
--- a/ui/wm/core/shadow_controller_unittest.cc
+++ b/ui/wm/core/shadow_controller_unittest.cc
@@ -13,6 +13,7 @@
 #include "ui/aura/window.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/compositor/layer.h"
+#include "ui/wm/core/default_activation_client.h"
 #include "ui/wm/core/shadow.h"
 #include "ui/wm/core/shadow_types.h"
 #include "ui/wm/core/window_util.h"
@@ -29,6 +30,7 @@ class ShadowControllerTest : public aura::test::AuraTestBase {
   virtual void SetUp() OVERRIDE {
     wm_state_.reset(new wm::WMState);
     AuraTestBase::SetUp();
+    new wm::DefaultActivationClient(root_window());
     aura::client::ActivationClient* activation_client =
         aura::client::GetActivationClient(root_window());
     shadow_controller_.reset(new ShadowController(activation_client));