Another attempt at fixing the fullscreen issues with Chrome.

ui/views/win/fullscreen_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/fullscreen_handler.h"
 
 #include <memory>
 
 #include "base/logging.h"
 #include "base/win/win_util.h"
@@ skipping 67 matching lines @@
     // repainted.  Better-looking methods welcome.
     SetWindowLong(hwnd_, GWL_STYLE, saved_window_info_.style);
     SetWindowLong(hwnd_, GWL_EXSTYLE, saved_window_info_.ex_style);
 
     // On restore, resize to the previous saved rect size.
     gfx::Rect new_rect(saved_window_info_.window_rect);
     SetWindowPos(hwnd_, NULL, new_rect.x(), new_rect.y(), new_rect.width(),
                  new_rect.height(),
                  SWP_NOZORDER | SWP_NOACTIVATE | SWP_FRAMECHANGED);
   }
+
+  if (!task_bar_list_) {
+    HRESULT hr = ::CoCreateInstance(CLSID_TaskbarList, NULL,
+                                    CLSCTX_INPROC_SERVER,
+                                    IID_PPV_ARGS(&task_bar_list_));
+    CHECK(SUCCEEDED(hr));
+  }
+
+  // As per MSDN marking the window as fullscreen should ensure that the
+  // taskbar is moved to the bottom of the Z-order when the fullscreen window
+  // is activated. If the window is not fullscreen, the Shell falls back to
+  // heuristics to determine how the window should be treated, which means
+  // that it could still consider the window as fullscreen. :(
+  task_bar_list_->MarkFullscreenWindow(hwnd_, !!fullscreen);
 }
 
 }  // namespace views