Respect the system ClearType setting in RenderTextWin.

ui/base/win/singleton_hwnd.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/singleton_hwnd.h"
+
+#include "base/memory/singleton.h"
+#include "base/process_util.h"
+#include "base/win/wrapped_window_proc.h"
+#include "ui/base/win/hwnd_util.h"
+
+namespace {
+
+// Windows class name to use for the listener window.
+const wchar_t kWindowClassName[] = L"Chrome_SingletonHwnd";
+
+// Windows callback for listening for WM_* messages.
+LRESULT CALLBACK ListenerWindowProc(HWND hwnd,
+                                    UINT message,
+                                    WPARAM wparam,
+                                    LPARAM lparam) {
+  ui::SingletonHwnd::GetInstance()->OnWndProc(hwnd, message, wparam, lparam);
+  return ::DefWindowProc(hwnd, message, wparam, lparam);
+}
+
+// Creates a listener window to receive WM_* messages.
+HWND CreateListenerWindow() {
+  WNDCLASSEX wc = {0};
+  wc.cbSize = sizeof(wc);
+  wc.lpfnWndProc = base::win::WrappedWindowProc<ListenerWindowProc>;
+  wc.hInstance = base::GetModuleFromAddress(&ListenerWindowProc);
+  wc.lpszClassName = kWindowClassName;
+  ATOM window_class = ::RegisterClassEx(&wc);
+  DCHECK(window_class);
+
+  return ::CreateWindow(MAKEINTATOM(window_class), 0, 0, 0, 0, 0, 0, 0, 0,
+                        wc.hInstance, 0);
+}
+
+}  // namespace
+
+namespace ui {
+
+// static
+SingletonHwnd* SingletonHwnd::GetInstance() {
+  return Singleton<SingletonHwnd>::get();
+}
+
+void SingletonHwnd::AddObserver(Observer* observer) {
+  if (!listener_window_) {
+    listener_window_ = CreateListenerWindow();
+    ui::CheckWindowCreated(listener_window_);
+  }
+  observer_list_.AddObserver(observer);
+}
+
+void SingletonHwnd::RemoveObserver(Observer* observer) {
+  observer_list_.RemoveObserver(observer);
+}
+
+void SingletonHwnd::OnWndProc(HWND hwnd,
+                              UINT message,
+                              WPARAM wparam,
+                              LPARAM lparam) {
+  FOR_EACH_OBSERVER(Observer,
+                    observer_list_,
+                    OnWndProc(hwnd, message, wparam, lparam));
+}
+
+SingletonHwnd::SingletonHwnd()
+    : listener_window_(NULL) {
+}
+
+SingletonHwnd::~SingletonHwnd() {
+  if (listener_window_) {
+    ::DestroyWindow(listener_window_);
+    ::UnregisterClass(kWindowClassName, GetModuleHandle(NULL));
+  }
+}
+
+}  // namespace ui