Added classes to enable session sync functionality.

chrome/common/chrome_switches.h

Index: chrome/common/chrome_switches.h
diff --git a/chrome/common/chrome_switches.h b/chrome/common/chrome_switches.h
index 8fa9a2dd5a6f2fec495669359043ea1c6c3608bb..df9b9526e3a81e15baff63eaa37576fc3fb9e08e 100644
--- a/chrome/common/chrome_switches.h
+++ b/chrome/common/chrome_switches.h
@@ -87,6 +87,7 @@ extern const char kDisableSyncPasswords[];
 extern const char kDisableSyncPreferences[];
 extern const char kDisableSyncThemes[];
 extern const char kDisableSyncTypedUrls[];
+extern const char kDisableSyncSessions[];
 extern const char kDisableTabCloseableStateWatcher[];
 extern const char kDisableWebResources[];
 extern const char kDisableWebSecurity[];
@@ -140,6 +141,7 @@ extern const char kEnableSyncBookmarks[];
 extern const char kEnableSyncExtensions[];
 extern const char kEnableSyncPasswords[];
 extern const char kEnableSyncPreferences[];
+extern const char kEnableSyncSessions[];
 extern const char kEnableSyncThemes[];
 extern const char kEnableSyncTypedUrls[];
 extern const char kEnableTabbedOptions[];