Fix the painting problems seen in the tabstrip when switching from a theme to glass on Windows.

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 799 matching lines @@
     // frame to a native frame.  If we don't, the client area will be filled
     // with black.  This seems to be related to an interaction between DWM and
     // SetWindowRgn, but the details aren't clear. Additionally, we need to
     // specify SWP_NOZORDER here, otherwise if you have multiple chrome windows
     // open they will re-appear with a non-deterministic Z-order.
     UINT flags = SWP_NOMOVE | SWP_NOSIZE | SWP_NOZORDER;
     SetWindowPos(hwnd(), NULL, 0, 0, 0, 0, flags | SWP_HIDEWINDOW);
     SetWindowPos(hwnd(), NULL, 0, 0, 0, 0, flags | SWP_SHOWWINDOW);
     // Invalidate the window to force a paint. There may be child windows which
     // could resize in this context. Don't paint right away.
-    ::InvalidateRect(hwnd(), NULL, FALSE);
+    base::MessageLoop::current()->PostDelayedTask(
+      FROM_HERE,
+      base::Bind(base::IgnoreResult(&::InvalidateRect), hwnd(),
+                 reinterpret_cast<const RECT*>(NULL), FALSE),
+      base::TimeDelta::FromMilliseconds(500));

[ananta, 2014/08/05 00:24:03]

It now appears that the bug was never fixed. We need to merge this to M37.

[sky, 2014/08/05 01:30:56]

This is a total hack. Why do we need to delay?
Also, I don't like posting to a potentially deleted window.

   }
 
   // WM_DWMCOMPOSITIONCHANGED is only sent to top level windows, however we want
   // to notify our children too, since we can have MDI child windows who need to
   // update their appearance.
   EnumChildWindows(hwnd(), &SendDwmCompositionChanged, NULL);
 }
 
 void HWNDMessageHandler::SchedulePaintInRect(const gfx::Rect& rect) {
   if (use_layered_buffer_) {
     // We must update the back-buffer immediately, since Windows' handling of
     // invalid rects is somewhat mysterious.
     invalid_rect_.Union(rect);
 
     // In some situations, such as drag and drop, when Windows itself runs a
     // nested message loop our message loop appears to be starved and we don't
     // receive calls to DidProcessMessage(). This only seems to affect layered
     // windows, so we schedule a redraw manually using a task, since those never
     // seem to be starved. Also, wtf.
     if (!waiting_for_redraw_layered_window_contents_) {
       waiting_for_redraw_layered_window_contents_ = true;
       base::MessageLoop::current()->PostTask(
           FROM_HERE,
-          base::Bind(&HWNDMessageHandler::RedrawLayeredWindowContents,
+          base::Bind(base::IgnoreResult(&HWNDMessageHandler::RedrawLayeredWindowContents),
                      weak_factory_.GetWeakPtr()));
     }
   } else {
     // InvalidateRect() expects client coordinates.
     RECT r = rect.ToRECT();
     InvalidateRect(hwnd(), &r, FALSE);
   }
 }
 
 void HWNDMessageHandler::SetOpacity(BYTE opacity) {
@@ skipping 1582 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