Provide mutable members of UrlRequestContext via pure-virtual interface

chrome/browser/io_thread.h

Index: chrome/browser/io_thread.h
diff --git a/chrome/browser/io_thread.h b/chrome/browser/io_thread.h
index 180ae24951e3ab85ae859f564bca7bf4438d78a2..c76887c7a22ad89e4c1861e0f7e874cd7aa77953 100644
--- a/chrome/browser/io_thread.h
+++ b/chrome/browser/io_thread.h
@@ -22,6 +22,7 @@ class ChromeNetLog;
 class PrefProxyConfigTrackerImpl;
 class PrefService;
 class SystemURLRequestContextGetter;
+class BasicHttpUserAgentSettings;
 
 namespace chrome_browser_net {
 class HttpPipeliningCompatibilityClient;
@@ -115,6 +116,7 @@ class IOThread : public content::BrowserThreadDelegate {
         http_pipelining_compatibility_client;
     scoped_ptr<chrome_browser_net::LoadTimeStats> load_time_stats;
     scoped_ptr<net::HostMappingRules> host_mapping_rules;
+    scoped_ptr<BasicHttpUserAgentSettings> basic_http_user_agent_settings;

[erikwright (departed), 2012/09/25 21:06:38]

Does this need to be the derived type?

[pauljensen, 2012/09/26 14:08:19]

It doesn't need to be but it seems like the most debugable choice.  I don't have
a preference otherwise.

[erikwright (departed), 2012/09/26 14:19:36]

OK. I think the convention would be to use the least derived type possible to
promote encapsulation. It also makes it easier to change the implementation
later.

     bool ignore_certificate_errors;
     bool http_pipelining_enabled;
     uint16 testing_fixed_http_port;