Make SDCH dictionaries persistent across browser restart.

net/url_request/sdch_dictionary_fetcher.h

Index: net/url_request/sdch_dictionary_fetcher.h
diff --git a/net/url_request/sdch_dictionary_fetcher.h b/net/url_request/sdch_dictionary_fetcher.h
index 4ca25034e8e5467a7082c9efd18b40e77017eb20..eb3a542d3cc717c2699cda28d6227612672e3a83 100644
--- a/net/url_request/sdch_dictionary_fetcher.h
+++ b/net/url_request/sdch_dictionary_fetcher.h
@@ -45,15 +45,18 @@ class NET_EXPORT SdchDictionaryFetcher : public URLRequest::Delegate,
       OnDictionaryFetchedCallback;
 
   // The consumer must guarantee that |*context| outlives this object.
-  // |callback| will be called on successful dictionary fetch
-  // requested through Schedule().  |callback| will not be called
-  // after object destruction.
-  SdchDictionaryFetcher(URLRequestContext* context,
-                        const OnDictionaryFetchedCallback& callback);
+  SdchDictionaryFetcher(URLRequestContext* context);

[mmenke, 2015/02/12 20:40:36]

explicit

[Elly Fong-Jones, 2015/02/13 23:35:01]

Done.

   ~SdchDictionaryFetcher() override;
 
-  // Request a new dictionary fetch.
-  void Schedule(const GURL& dictionary_url);
+  // Request a new dictionary fetch.  The callback will be called
+  // only if the dictionary is successfully fetched.
+  void Schedule(const GURL& dictionary_url,
+                const OnDictionaryFetchedCallback& callback);
+
+  // Request a dictionary fetch from cache only.  The callback will be called
+  // only if the dictionary is successfully fetched.
+  void ScheduleReload(const GURL& dictionary_url,
+                      const OnDictionaryFetchedCallback& callback);
 
   // Cancel any in-progress requests.
   void Cancel();
@@ -72,6 +75,30 @@ class NET_EXPORT SdchDictionaryFetcher : public URLRequest::Delegate,
     STATE_REQUEST_COMPLETE,
   };
 
+  struct QueuedInfo {

[mmenke, 2015/02/12 20:40:36]

QueuedFetchInfo?  And maybe a quick comment...

[Elly Fong-Jones, 2015/02/13 23:35:01]

Done.

+    GURL url;
+    bool download_only_from_cache;
+    OnDictionaryFetchedCallback callback;

[mmenke, 2015/02/12 20:40:36]

Member variables should go after methods.

[Elly Fong-Jones, 2015/02/13 23:35:01]

Done.

+
+    QueuedInfo();
+    QueuedInfo(const GURL& url,
+               bool download_only_from_cache,
+               const OnDictionaryFetchedCallback& callback);
+    QueuedInfo(const QueuedInfo& rhs);
+    QueuedInfo& operator=(const QueuedInfo& rhs);

[mmenke, 2015/02/12 20:40:36]

Hrm....  Per style guide, constructor and destructor should go first...  Doesn't
say anything about operator=...  Does seem to make sense with the constructors,
though, so I'm fine either way, jsut thought I'd mention it.

[Elly Fong-Jones, 2015/02/13 23:35:01]

Done.

+
+    ~QueuedInfo();
+  };
+
+  // Schedule implementation.
+  void ScheduleInternal(const GURL& dictionary_url,
+                        bool reload,
+                        const OnDictionaryFetchedCallback& callback);
+
+  // Null out the current request and push the state machine to the
+  // next request, if any.
+  void ResetRequest();
+
   // State machine implementation.
   int DoLoop(int rv);
   int DoSendRequest(int rv);
@@ -84,12 +111,15 @@ class NET_EXPORT SdchDictionaryFetcher : public URLRequest::Delegate,
   bool in_loop_;
 
   // A queue of URLs that are being used to download dictionaries.
-  std::queue<GURL> fetch_queue_;
+  // |fetch_queue_[n].second| indicated whether the download should occur

[mmenke, 2015/02/12 20:40:36]

second -> download_only_from_cache

[Elly Fong-Jones, 2015/02/13 23:35:01]

Done.

+  // only from cache.
+  std::queue<QueuedInfo> fetch_queue_;
 
-  // The request and buffer used for getting the current dictionary
-  // Both are null when a fetch is not in progress.
+  // The request, buffer, and consumer supplied data used for getting
+  // the current dictionary.  All are null when a fetch is not in progress.
   scoped_ptr<URLRequest> current_request_;
   scoped_refptr<IOBuffer> buffer_;
+  OnDictionaryFetchedCallback current_callback_;
 
   // The currently accumulating dictionary.
   std::string dictionary_;
@@ -113,8 +143,6 @@ class NET_EXPORT SdchDictionaryFetcher : public URLRequest::Delegate,
   // use while fetching.
   URLRequestContext* const context_;
 
-  const OnDictionaryFetchedCallback dictionary_fetched_callback_;
-
   base::WeakPtrFactory<SdchDictionaryFetcher> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SdchDictionaryFetcher);