Move pref_{member,service} and important_file_writer from chrome/common
to chrome/browser.

This is a part of an effort to remove bad dependency of chrome/common
on chrome/browser.

TEST=unit_tests and ui_tests, just moving code
BUG=none
Review URL: http://codereview.chromium.org/621004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@39428 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/browser/extensions/extensions_service.cc b/chrome/browser/extensions/extensions_service.cc
index 476f640f..7b98410 100644
--- a/chrome/browser/extensions/extensions_service.cc
+++ b/chrome/browser/extensions/extensions_service.cc
@@ -25,6 +25,7 @@
 #include "chrome/browser/extensions/extension_updater.h"
 #include "chrome/browser/extensions/external_extension_provider.h"
 #include "chrome/browser/extensions/external_pref_extension_provider.h"
+#include "chrome/browser/pref_service.h"
 #include "chrome/browser/profile.h"
 #include "chrome/browser/net/chrome_url_request_context.h"
 #include "chrome/common/child_process_logging.h"
@@ -36,7 +37,6 @@
 #include "chrome/common/notification_service.h"
 #include "chrome/common/notification_type.h"
 #include "chrome/common/pref_names.h"
-#include "chrome/common/pref_service.h"
 #include "chrome/common/url_constants.h"
 
 #if defined(OS_WIN)