Fix aura flickering when not using DWM.

ui/views/widget/desktop_aura/desktop_root_window_host_win.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/desktop_aura/desktop_root_window_host_win.h"
 
 #include "base/win/metro.h"
 #include "third_party/skia/include/core/SkPath.h"
 #include "third_party/skia/include/core/SkRegion.h"
 #include "ui/aura/client/aura_constants.h"
@@ skipping 372 matching lines @@
 
 void DesktopRootWindowHostWin::OnNativeWidgetFocus() {
   // HWNDMessageHandler will perform the proper updating on its own.
 }
 
 void DesktopRootWindowHostWin::OnNativeWidgetBlur() {
 }
 
 void DesktopRootWindowHostWin::SetInactiveRenderingDisabled(
     bool disable_inactive) {
-  // We call DefWindowProc of WM_NCACTIVATE to paint the caption as active or
-  // inactive. This is safe with the only sideeffect being the
-  // WM_GETTEXT message which is sent by DefWindowProc to get the text to be
-  // displayed on the caption.
-  ::DefWindowProc(message_handler_->hwnd(),
-                  WM_NCACTIVATE,
-                  !!disable_inactive,
-                  0);
+  // Force the non-client area (most notably the title bar) to paint as either
+  // active or inactive, depending on the input.
+  SendMessage(message_handler_->hwnd(), WM_NCACTIVATE, !!disable_inactive, 0);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 // DesktopRootWindowHostWin, RootWindowHost implementation:
 
 
 void DesktopRootWindowHostWin::SetDelegate(
     aura::RootWindowHostDelegate* delegate) {
   root_window_host_delegate_ = delegate;
 }
@@ skipping 478 matching lines @@
 DesktopRootWindowHost* DesktopRootWindowHost::Create(
     internal::NativeWidgetDelegate* native_widget_delegate,
     DesktopNativeWidgetAura* desktop_native_widget_aura,
     const gfx::Rect& initial_bounds) {
   return new DesktopRootWindowHostWin(native_widget_delegate,
                                       desktop_native_widget_aura,
                                       initial_bounds);
 }
 
 }  // namespace views