Introduce //components/user_prefs, use to eliminate c/b/prefs dependency in Autofill.

chrome/browser/profiles/profile_manager.cc

Index: chrome/browser/profiles/profile_manager.cc
diff --git a/chrome/browser/profiles/profile_manager.cc b/chrome/browser/profiles/profile_manager.cc
index c08f9a11e1535547eb4fda5079b10e9a69d73b70..52e6a7610a31ea827f7a8adf3eff865ae2b7bd34 100644
--- a/chrome/browser/profiles/profile_manager.cc
+++ b/chrome/browser/profiles/profile_manager.cc
@@ -36,6 +36,8 @@
 #include "chrome/common/logging_chrome.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/common/url_constants.h"
+#include "components/user_prefs/user_prefs.h"
+#include "components/user_prefs/user_prefs_delegate.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/user_metrics.h"
@@ -171,6 +173,20 @@ void CheckCryptohomeIsMounted(chromeos::DBusMethodCallStatus call_status,
 }
 #endif
 
+class ChromeUserPrefsDelegate : public components::UserPrefsDelegate {
+ public:
+  ChromeUserPrefsDelegate() {}
+  virtual ~ChromeUserPrefsDelegate() {}
+
+  virtual PrefService* PrefServiceFromBrowserContext(
+      content::BrowserContext* context) OVERRIDE {
+    return static_cast<Profile*>(context)->GetPrefs();
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ChromeUserPrefsDelegate);
+};
+
 } // namespace
 
 #if defined(ENABLE_SESSION_SERVICE)
@@ -267,6 +283,10 @@ ProfileManager::ProfileManager(const base::FilePath& user_data_dir)
   if (ProfileShortcutManager::IsFeatureEnabled() && !user_data_dir.empty())
     profile_shortcut_manager_.reset(ProfileShortcutManager::Create(
                                     this));
+
+  components::UserPrefs::GetInstance()->Initialize(
+      scoped_ptr<components::UserPrefsDelegate>(
+          new ChromeUserPrefsDelegate).Pass());
 }
 
 ProfileManager::~ProfileManager() {