Hide/show widget on Windows screen lock/unlock

ui/views/win/hwnd_message_handler.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 "ui/views/win/hwnd_message_handler.h"
 
 #include <dwmapi.h>
 #include <oleacc.h>
 #include <shellapi.h>
 #include <tchar.h>
@@ skipping 2283 matching lines @@
   if (sent_window_size_changing_) {
     sent_window_size_changing_ = false;
     delegate_->HandleWindowSizeChanged();
   }
   SetMsgHandled(FALSE);
 }
 
 void HWNDMessageHandler::OnSessionChange(WPARAM status_code) {
   // Direct3D presents are ignored while the screen is locked, so force the
   // window to be redrawn on unlock.
-  if (status_code == WTS_SESSION_UNLOCK)
+  if (status_code == WTS_SESSION_UNLOCK) {
     ForceRedrawWindow(10);
+    if (IsVisible())
+      delegate_->HandleSoftVisibilityChanged(true);
+  } else if (status_code == WTS_SESSION_LOCK) {
+    if (IsVisible())
+      delegate_->HandleSoftVisibilityChanged(false);
+  }
 }
 
 void HWNDMessageHandler::HandleTouchEvents(const TouchEvents& touch_events) {
   base::WeakPtr<HWNDMessageHandler> ref(weak_factory_.GetWeakPtr());
   for (size_t i = 0; i < touch_events.size() && ref; ++i)
     delegate_->HandleTouchEvent(touch_events[i]);
 }
 
 void HWNDMessageHandler::ResetTouchDownContext() {
   touch_down_contexts_--;
@@ skipping 314 matching lines @@
     delegate_->HandleClientSizeChanged(GetClientAreaBounds().size());
     ResetWindowRegion(false, true);
   }
 
   if (direct_manipulation_helper_)
     direct_manipulation_helper_->SetBounds(bounds_in_pixels);
 }
 
 
 }  // namespace views