Simplify threading in browser thread by making only ChromeThread deal with di...

chrome/browser/net/url_fetcher.h

 // Copyright (c) 2009 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.
 //
 // This file contains URLFetcher, a wrapper around URLRequest that handles
 // low-level details like thread safety, ref counting, and incremental buffer
 // reading.  This is useful for callers who simply want to get the data from a
 // URL and don't care about all the nitty-gritty details.
 
 #ifndef CHROME_BROWSER_URL_FETCHER_H_
@@ skipping 30 matching lines @@
 // resulting status and (if applicable) HTTP response code.  From that point
 // until the original URLFetcher instance is destroyed, you may examine the
 // provided status and data for the URL.  (You should copy these objects if you
 // need them to live longer than the URLFetcher instance.)  If the URLFetcher
 // instance is destroyed before the callback happens, the fetch will be
 // canceled and no callback will occur.
 //
 // You may create the URLFetcher instance on any thread; OnURLFetchComplete()
 // will be called back on the same thread you use to create the instance.
 //
-// NOTE: Take extra care when using URLFetcher in services that live on the
-//       BrowserProcess; all URLFetcher instances need to be destroyed before
-//       the IO thread goes away, since the URLFetcher destructor requests an
-//       InvokeLater operation on that thread.
 //
 // NOTE: By default URLFetcher requests are NOT intercepted, except when
 // interception is explicitly enabled in tests.
 
 class URLFetcher {
  public:
   enum RequestType {
     GET,
     POST,
     HEAD,
@@ skipping 44 matching lines @@
     g_interception_enabled = enabled;
   }
 
   // Creates a URLFetcher, ownership returns to the caller. If there is no
   // Factory (the default) this creates and returns a new URLFetcher. See the
   // constructor for a description of the args. |id| may be used during testing
   // to identify who is creating the URLFetcher.
   static URLFetcher* Create(int id, const GURL& url, RequestType request_type,
                             Delegate* d);
 
-  // This should only be used by unittests, where g_browser_process->io_thread()
-  // does not exist and we must specify an alternate loop.  Unfortunately, we
-  // can't put it under #ifdef UNIT_TEST since some callers (which themselves
-  // should only be reached in unit tests) use this.  See
-  // chrome/browser/feeds/feed_manager.cc.
-  void set_io_loop(MessageLoop* io_loop);
-
   // Sets data only needed by POSTs.  All callers making POST requests should
   // call this before the request is started.  |upload_content_type| is the MIME
   // type of the content, while |upload_content| is the data to be sent (the
   // Content-Length header value will be set to the length of this data).
   void set_upload_data(const std::string& upload_content_type,
                        const std::string& upload_content);
 
   // Set one or more load flags as defined in net/base/load_flags.h.  Must be
   // called before the request is started.
   void set_load_flags(int load_flags);
@@ skipping 18 matching lines @@
   virtual void Start();
 
   // Return the URL that this fetcher is processing.
   const GURL& url() const;
 
  protected:
   // Returns the delegate.
   Delegate* delegate() const;
 
  private:
-  // This class is the real guts of URLFetcher.
-  //
-  // When created, delegate_loop_ is set to the message loop of the current
-  // thread, while io_loop_ is set to the message loop of the IO thread.  These
-  // are used to ensure that all handling of URLRequests happens on the IO
-  // thread (since that class is not currently threadsafe and relies on
-  // underlying Microsoft APIs that we don't know to be threadsafe), while
-  // keeping the delegate callback on the delegate's thread.
   class Core;
 
   scoped_refptr<Core> core_;
 
   static Factory* factory_;
 
   base::LeakTracker<URLFetcher> leak_tracker_;
 
   static bool g_interception_enabled;
 
   DISALLOW_EVIL_CONSTRUCTORS(URLFetcher);
 };
 
 #endif  // CHROME_BROWSER_URL_FETCHER_H_