Provide mutable members of UrlRequestContext via pure-virtual interface

chrome/browser/profiles/profile_io_data.cc

Index: chrome/browser/profiles/profile_io_data.cc
diff --git a/chrome/browser/profiles/profile_io_data.cc b/chrome/browser/profiles/profile_io_data.cc
index 78153f5e1371dbc29328b18a54d92590db72a41a..0ad6918767c8075cf4c6ebe04df25920ca12a288 100644
--- a/chrome/browser/profiles/profile_io_data.cc
+++ b/chrome/browser/profiles/profile_io_data.cc
@@ -31,6 +31,7 @@
 #include "chrome/browser/io_thread.h"
 #include "chrome/browser/net/chrome_cookie_notification_details.h"
 #include "chrome/browser/net/chrome_fraudulent_certificate_reporter.h"
+#include "chrome/browser/net/chrome_http_user_agent_settings.h"
 #include "chrome/browser/net/chrome_net_log.h"
 #include "chrome/browser/net/chrome_network_delegate.h"
 #include "chrome/browser/net/http_server_properties_manager.h"
@@ -144,12 +145,8 @@ void ProfileIOData::InitializeOnUIThread(Profile* profile) {
   scoped_ptr<ProfileParams> params(new ProfileParams);
   params->path = profile->GetPath();
 
-  // Set up Accept-Language and Accept-Charset header values
-  params->accept_language = net::HttpUtil::GenerateAcceptLanguageHeader(
-      pref_service->GetString(prefs::kAcceptLanguages));
-  std::string default_charset = pref_service->GetString(prefs::kDefaultCharset);
-  params->accept_charset =
-      net::HttpUtil::GenerateAcceptCharsetHeader(default_charset);
+  params->chrome_http_user_agent_settings.reset(
+      new ChromeHttpUserAgentSettings(pref_service));
 
   params->io_thread = g_browser_process->io_thread();
 
@@ -569,6 +566,9 @@ void ProfileIOData::LazyInitialize() const {
         profile_params_->resource_prefetch_predictor_observer_.release());
   }
 
+  chrome_http_user_agent_settings_.reset(
+      profile_params_->chrome_http_user_agent_settings.release());
+
   LazyInitializeInternal(profile_params_.get());
 
   profile_params_.reset();
@@ -578,8 +578,8 @@ void ProfileIOData::LazyInitialize() const {
 void ProfileIOData::ApplyProfileParamsToContext(
     ChromeURLRequestContext* context) const {
   context->set_is_incognito(is_incognito());
-  context->set_accept_language(profile_params_->accept_language);
-  context->set_accept_charset(profile_params_->accept_charset);
+  context->set_http_user_agent_settings(
+    chrome_http_user_agent_settings_.get());

[mmenke, 2012/10/25 18:06:33]

nit:  4 space indent.  Actually, can this all fit on one line?

   context->set_ssl_config_service(profile_params_->ssl_config_service);
 }
 
@@ -663,6 +663,8 @@ void ProfileIOData::ShutdownOnUIThread() {
   if (url_blacklist_manager_.get())
     url_blacklist_manager_->ShutdownOnUIThread();
 #endif
+  if (chrome_http_user_agent_settings_.get())
+    chrome_http_user_agent_settings_->CleanupOnUIThread();

[mmenke, 2012/10/25 18:06:33]

Doesn't this always need to be called?  Otherwise, it will access prefs_ on the
IO thread when it's deleted there.

Also, I don't believe this is threadsafe for another reason. 
chrome_http_user_agent_settings_ is initialized on the IO thread, and here we're
accessin it on the UI thread.  Is there any guarantee we don't have a
LazyInitialize() in progress when we reach this point?

Think you can just set chrome_http_user_agent_settings_ on construction.

[pauljensen, 2012/10/25 21:30:25]

I don't think we can construct ChromeHttpUserAgentSettings in ProfileIOData()
because the PrefService isn't constructed yet.  There are several alternatives:
1. We could construct ChromeHttpUserAgentSettings in ProfileIOData() and add
ChromeHttpUserAgentSettings::InitAfterPrefsLoaded() that we could call later.
2. We could construct ChromeHttpUserAgentSettings in
ProfileIODataImpl::Handle::Init() which is called from 
ProfileImpl::OnPrefsLoaded() but there isn't a corresponding 
OffTheRecordProfileImpl::Handle::Init().
3. We could construct ChromeHttpUserAgentSettings and set
chrome_http_user_agent_settings_ directly in
ProfileIOData::InitializeOnUIThread() instead of passing through the
profile_params_.  This way it can be initialized next to the other PrefMember
members of ProfileIOData.  This should avoid the threading issues.
4. We could yank the StringPrefMember's out of ChromeHttpUserAgentSettings and
put them in ProfileIOData, similar to enable_referrers_, and pass their
addresses into ChromeHttpUserAgentSettings().
I've implemented #3 because it seems to be the simplest and most
straightforward.

[mmenke, 2012/10/26 18:42:09]

Sounds like the best approach to me, too.

   bool posted = BrowserThread::DeleteSoon(BrowserThread::IO, FROM_HERE, this);
   if (!posted)
     delete this;