Update window region after widget resizes not changing HWND size

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 <wtsapi32.h>
@@ skipping 849 matching lines @@
   if (!app_icon.isNull()) {
     HICON windows_icon = IconUtil::CreateHICONFromSkBitmap(*app_icon.bitmap());
     HICON old_icon = reinterpret_cast<HICON>(
         SendMessage(hwnd(), WM_SETICON, ICON_BIG,
                     reinterpret_cast<LPARAM>(windows_icon)));
     if (old_icon)
       DestroyIcon(old_icon);
   }
 }
 
+void HWNDMessageHandler::ForceWindowResized() {
+  delegate_->HandleClientSizeChanged(GetClientAreaBounds().size());
+  ResetWindowRegion(false, true);
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // HWNDMessageHandler, InputMethodDelegate implementation:
 
 void HWNDMessageHandler::DispatchKeyEventPostIME(const ui::KeyEvent& key) {
   SetMsgHandled(delegate_->HandleKeyEvent(key));
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // HWNDMessageHandler, gfx::WindowImpl overrides:
 
@@ skipping 1530 matching lines @@
     POINT cursor_pos = {0};
     ::GetCursorPos(&cursor_pos);
     if (memcmp(&cursor_pos, &mouse_location, sizeof(POINT)))
       return false;
     return true;
   }
   return false;
 }
 
 }  // namespace views