Don't pass in WS_EX_TRANSPARENT in the window style in classic mode in AURA as that causes the wind…

ui/views/widget/widget_hwnd_utils.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/widget/widget_hwnd_utils.h"
 
 #include <dwmapi.h>
 
 #include "base/command_line.h"
 #include "base/win/windows_version.h"
@@ skipping 45 matching lines @@
   // and the desktop background. The handshake is as follows:
   // 1- Use D3D9Ex to create device/swapchain, etc. You need D3DFMT_A8R8G8B8.
   // 2- The window must have WS_EX_COMPOSITED in the extended style.
   // 3- The window must have WS_POPUP in its style.
   // 4- The windows must not have WM_SIZEBOX, WS_THICKFRAME or WS_CAPTION in its
   //    style.
   // 5- When the window is created but before it is presented, call
   //    DwmExtendFrameIntoClientArea passing -1 as the margins.
   if (params.opacity == Widget::InitParams::TRANSLUCENT_WINDOW) {
 #if defined(USE_AURA)
-    if (ui::win::IsAeroGlassEnabled())
+    if (ui::win::IsAeroGlassEnabled()) {
       *ex_style |= WS_EX_COMPOSITED;
+    } else {
+      // In classic mode, the WS_EX_TRANSPARENT style causes the window to not
+      // paint correctly.
+      *ex_style &= ~WS_EX_TRANSPARENT;

[sky, 2013/09/06 21:03:47]

Won't this cause bad things to happen where we are using WS_EX_TRANSPARENT?

[ananta, 2013/09/06 21:23:26]

The HWNDMessageHandler::SetInitialFocus function is the only place we need to
worry about, I think. It does not set focus if the window has either of the
WS_EX_TRANSPARENT or WS_EX_NOACTIVATE.
In any case as this style brings in bugs, we should not be using it.

[ananta, 2013/09/06 22:08:50]

As per our discussion we pass in accept_events = true when creating windows in
desktop AURA. I will look into the painting issues with transparent separately.

+    }
 #else
     *ex_style |= WS_EX_LAYERED;
 #endif
   }
   if (params.has_dropshadow) {
     *class_style |= (base::win::GetVersion() < base::win::VERSION_XP) ?
         0 : CS_DROPSHADOW;
   }
 
   // Set type-dependent style attributes.
@@ skipping 75 matching lines @@
   DWORD class_style = 0;
   CalculateWindowStylesFromInitParams(params, widget_delegate,
                                       native_widget_delegate, &style, &ex_style,
                                       &class_style);
   handler->set_initial_class_style(class_style);
   handler->set_window_style(handler->window_style() | style);
   handler->set_window_ex_style(handler->window_ex_style() | ex_style);
 }
 
 }  // namespace views