Enable immersive fullscreen on Windows Ash.

ash/wm/system_gesture_event_filter.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ash/wm/system_gesture_event_filter.h"
 
 #include "ash/ash_switches.h"
 #include "ash/metrics/user_metrics_recorder.h"
 #include "ash/shell.h"
 #include "ash/touch/touch_uma.h"
@@ skipping 47 matching lines @@
   long_press_affordance_->ProcessEvent(target, event);
 
   if (overview_gesture_handler_ &&
       overview_gesture_handler_->ProcessGestureEvent(*event)) {
     event->StopPropagation();
     return;
   }
 
   if (event->type() == ui::ET_GESTURE_WIN8_EDGE_SWIPE &&
       shelf_gesture_handler_->ProcessGestureEvent(*event)) {
-    event->StopPropagation();
+    // Do not stop propagation, since the immersive fullscreen controller may
+    // need to handle this event.
+    return;
   }
 }
 
 }  // namespace internal
 }  // namespace ash