Broadcast NotifyTimezoneChange to all RenderProcessHosts when the system time zone changes

content/browser/time_zone_monitor_win.cc

+// Copyright 2014 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 "content/browser/time_zone_monitor.h"
+
+#include <windows.h>
+
+#include "base/basictypes.h"
+#include "ui/gfx/win/singleton_hwnd.h"
+
+namespace content {
+
+class TimeZoneMonitorWin : public TimeZoneMonitor,
+                           public gfx::SingletonHwnd::Observer {
+ public:
+  TimeZoneMonitorWin() : TimeZoneMonitor() {
+    gfx::SingletonHwnd::GetInstance()->AddObserver(this);
+  }
+
+  virtual ~TimeZoneMonitorWin() {
+    gfx::SingletonHwnd::GetInstance()->RemoveObserver(this);
+  }
+
+  // gfx::SingletonHwnd::Observer implementation.
+  virtual void OnWndProc(HWND hwnd,
+                         UINT message,
+                         WPARAM wparam,
+                         LPARAM lparam) OVERRIDE {
+    if (message != WM_TIMECHANGE) {
+      return;
+    }
+
+    NotifyRenderers();
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(TimeZoneMonitorWin);
+};
+
+// static
+scoped_ptr<TimeZoneMonitor> TimeZoneMonitor::Create() {
+  return scoped_ptr<TimeZoneMonitor>(new TimeZoneMonitorWin());
+}
+
+}  // namespace content