Restructure SDCH layering to allow more separation (observer/1->[0,n]

chrome/browser/net/chrome_sdch_policy.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 "chrome/browser/net/chrome_sdch_policy.h"
+
+#include "base/bind.h"
+#include "net/base/sdch_manager.h"
+
+ChromeSdchPolicy::ChromeSdchPolicy(net::SdchManager* sdch_manager,
+                                   net::URLRequestContext* context)
+    : manager_(sdch_manager),
+      // Because |fetcher_| is owned by ChromeSdchPolicy, the
+      // ChromeSdchPolicy object will be available for the lifetime
+      // of |fetcher_|.
+      fetcher_(context,
+               base::Bind(&ChromeSdchPolicy::OnDictionaryFetched,
+                          base::Unretained(this))) {
+  manager_->AddObserver(this);
+}
+
+ChromeSdchPolicy::~ChromeSdchPolicy() {
+  manager_->RemoveObserver(this);
+}
+
+void ChromeSdchPolicy::OnDictionaryFetched(const std::string& dictionary_text,
+                                           const GURL& dictionary_url) {
+  manager_->AddSdchDictionary(dictionary_text, dictionary_url);
+}
+
+void ChromeSdchPolicy::OnGetDictionary(net::SdchManager* manager,
+                                       const GURL& request_url,
+                                       const GURL& dictionary_url) {
+  fetcher_.Schedule(dictionary_url);
+}
+
+void ChromeSdchPolicy::OnClearDictionaries(net::SdchManager* manager) {
+  fetcher_.Cancel();
+}