Moves WorkspaceEventHandler to ash/common

ash/ash.gyp

Index: ash/ash.gyp
diff --git a/ash/ash.gyp b/ash/ash.gyp
index 68006f56ddf168fe3e923bd3894c04935ff31cbf..ad707a9db5afc8214e59f76cd10959ae0bd023ee 100644
--- a/ash/ash.gyp
+++ b/ash/ash.gyp
@@ -518,6 +518,8 @@
       'common/wm/workspace/phantom_window_controller.h',
       'common/wm/workspace/two_step_edge_cycler.cc',
       'common/wm/workspace/two_step_edge_cycler.h',
+      'common/wm/workspace/workspace_event_handler.cc',
+      'common/wm/workspace/workspace_event_handler.h',
       'common/wm/workspace/workspace_layout_manager.cc',
       'common/wm/workspace/workspace_layout_manager.h',
       'common/wm/workspace/workspace_layout_manager_backdrop_delegate.h',
@@ -803,8 +805,8 @@
       'wm/window_state_aura.h',
       'wm/window_util.cc',
       'wm/window_util.h',
-      'wm/workspace/workspace_event_handler.cc',
-      'wm/workspace/workspace_event_handler.h',
+      'wm/workspace/workspace_event_handler_aura.cc',
+      'wm/workspace/workspace_event_handler_aura.h',
       'wm/workspace_controller.cc',
       'wm/workspace_controller.h',
     ],
@@ -979,6 +981,8 @@
       'common/system/update/tray_update_unittest.cc',
       'common/system/user/tray_user_unittest.cc',
       'common/wm/overview/cleanup_animation_observer_unittest.cc',
+      'common/wm/workspace/workspace_event_handler_test_helper.cc',
+      'common/wm/workspace/workspace_event_handler_test_helper.h',
       'content/display/screen_orientation_controller_chromeos_unittest.cc',
       'content/keyboard_overlay/keyboard_overlay_delegate_unittest.cc',
       'content/keyboard_overlay/keyboard_overlay_view_unittest.cc',
@@ -1076,8 +1080,6 @@
       'wm/window_util_unittest.cc',
       'wm/workspace/magnetism_matcher_unittest.cc',
       'wm/workspace/multi_window_resize_controller_unittest.cc',
-      'wm/workspace/workspace_event_handler_test_helper.cc',
-      'wm/workspace/workspace_event_handler_test_helper.h',
       'wm/workspace/workspace_event_handler_unittest.cc',
       'wm/workspace/workspace_layout_manager_unittest.cc',
       'wm/workspace/workspace_window_resizer_unittest.cc',