Fix bug 105043: Panels [WIN]: For minimize panels, taskbar hover preview show the 4-pixel represent…

ui/base/win/hwnd_subclass.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/base/win/hwnd_subclass.h"
 
 #include "base/logging.h"
 #include "ui/base/win/hwnd_util.h"
 
 namespace {
@@ skipping 22 matching lines @@
 namespace ui {
 
 HWNDSubclass::HWNDSubclass(HWND target)
     : target_(target),
       original_wnd_proc_(GetCurrentWndProc(target)),
       ALLOW_THIS_IN_INITIALIZER_LIST(prop_(target, kHWNDSubclassKey, this)) {
   ui::SetWindowProc(target_, &WndProc);
 }
 
 HWNDSubclass::~HWNDSubclass() {
+  ui::SetWindowProc(target_, original_wnd_proc_);

[Ben Goodger (Google), 2012/05/22 23:05:48]

this is actually intentionally not done. the issue is the window can be further
subclassed, so there's no safe way to unsubclass. once you've subclassed, you
have to stick around for the life of the window.

[jianli, 2012/05/22 23:34:04]

Done.

 }
 
 void HWNDSubclass::SetFilter(HWNDMessageFilter* filter) {
   filter_.reset(filter);
 }
 
 LRESULT HWNDSubclass::OnWndProc(HWND hwnd,
                                 UINT message,
                                 WPARAM w_param,
                                 LPARAM l_param) {
   if (filter_.get()) {
     LRESULT l_result = 0;
     if (filter_->FilterMessage(hwnd, message, w_param, l_param, &l_result))
       return l_result;
   }
 
   // In most cases, |original_wnd_proc_| will take care of calling
   // DefWindowProc.
   return CallWindowProc(original_wnd_proc_, hwnd, message, w_param, l_param);
 }
 
 }  // namespace ui