Convert ViewMsg_NetworkStateChanged from routed -> control,

minimizing the number of required IPCs (since the online state
is a per-WebKit singleton).

In doing so, I've disentangled online state management from TabContents:
it now resides off by itself in BrowserOnlineStateObserver, a tiny class
owned by BrowserProcessImpl.

This is an attempt to re-land r91390 without the OnProcessLaunched IPC
(since r92062 solved that in a different way by using WebPreferences).
The previous commit was reverted due to missing message_loop.h includes.

R=darin@chromium.org

Review URL: http://codereview.chromium.org/7343011

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@92233 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 51 insertions, 0 deletions

diff --git a/content/browser/net/browser_online_state_observer.cc b/content/browser/net/browser_online_state_observer.cc
new file mode 100644
index 0000000..2b0ccd8
--- /dev/null
+++ b/content/browser/net/browser_online_state_observer.cc
@@ -0,0 +1,24 @@
+// Copyright (c) 2011 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/net/browser_online_state_observer.h"
+
+#include "content/browser/renderer_host/render_process_host.h"
+#include "content/common/view_messages.h"
+#include "net/base/network_change_notifier.h"
+
+BrowserOnlineStateObserver::BrowserOnlineStateObserver() {
+  net::NetworkChangeNotifier::AddOnlineStateObserver(this);
+}
+
+BrowserOnlineStateObserver::~BrowserOnlineStateObserver() {
+  net::NetworkChangeNotifier::RemoveOnlineStateObserver(this);
+}
+
+void BrowserOnlineStateObserver::OnOnlineStateChanged(bool online) {
+  for (RenderProcessHost::iterator it(RenderProcessHost::AllHostsIterator());
+       !it.IsAtEnd(); it.Advance()) {
+    it.GetCurrentValue()->Send(new ViewMsg_NetworkStateChanged(online));
+  }
+}
diff --git a/content/browser/net/browser_online_state_observer.h b/content/browser/net/browser_online_state_observer.h
new file mode 100644
index 0000000..1e5e71a
--- /dev/null
+++ b/content/browser/net/browser_online_state_observer.h
@@ -0,0 +1,27 @@
+// Copyright (c) 2011 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.
+
+#ifndef CONTENT_BROWSER_NET_BROWSER_ONLINE_STATE_OBSERVER_H_
+#define CONTENT_BROWSER_NET_BROWSER_ONLINE_STATE_OBSERVER_H_
+#pragma once
+
+#include "base/basictypes.h"
+#include "net/base/network_change_notifier.h"
+
+// Listens for changes to the online state and manages sending
+// updates to each RenderProcess via RenderProcessHost IPC.
+class BrowserOnlineStateObserver
+    : public net::NetworkChangeNotifier::OnlineStateObserver {
+ public:
+  BrowserOnlineStateObserver();
+  virtual ~BrowserOnlineStateObserver();
+
+  // OnlineStateObserver implementation.
+  virtual void OnOnlineStateChanged(bool online);
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(BrowserOnlineStateObserver);
+};
+
+#endif  // CONTENT_BROWSER_NET_BROWSER_ONLINE_STATE_OBSERVER_H_