Move UserActivityDetector from ash/wm/ to ui/wm/core/.

ui/wm/core/user_activity_detector.cc

Index: ui/wm/core/user_activity_detector.cc
diff --git a/ash/wm/user_activity_detector.cc b/ui/wm/core/user_activity_detector.cc
similarity index 96%
rename from ash/wm/user_activity_detector.cc
rename to ui/wm/core/user_activity_detector.cc
index 2809bb5b2a590dc68b85b81a654425fd8348500c..250e32b17145f1bc042c4dc0d447d08914927ca8 100644
--- a/ash/wm/user_activity_detector.cc
+++ b/ui/wm/core/user_activity_detector.cc
@@ -2,15 +2,15 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "ash/wm/user_activity_detector.h"
+#include "ui/wm/core/user_activity_detector.h"
 
-#include "ash/wm/user_activity_observer.h"
 #include "base/format_macros.h"
 #include "base/logging.h"
 #include "base/strings/stringprintf.h"
 #include "ui/events/event.h"
+#include "ui/wm/core/user_activity_observer.h"
 
-namespace ash {
+namespace wm {
 
 namespace {
 
@@ -109,4 +109,4 @@ void UserActivityDetector::HandleActivity(const ui::Event* event) {
   }
 }
 
-}  // namespace ash
+}  // namespace wm