Update Login Module.

- Added an API to mange user OAuth authentication.
   - Updated the Filter to use the new API.
   - Updated the Module to initialize if it needed the storages needed by the login module.
   - Updated gmail callback to use the new API.
   - Added a Persistence Layer

CMS_USER_API
   - clean api and related persistence code.

modules/login/cms_user_oauth_api.e

@@ -0,0 +1,64 @@
+note
+	description: "[
+		API to manage CMS User OAuth authentication.
+	]"
+	date: "$Date$"
+	revision: "$Revision$"
+
+class
+	CMS_USER_OAUTH_API
+
+inherit
+	CMS_MODULE_API
+
+	REFACTORING_HELPER
+
+create {LOGIN_MODULE}
+	make_with_storage
+
+feature {NONE} -- Initialization
+
+	make_with_storage (a_api: CMS_API; a_user_oauth_storage: CMS_USER_OAUTH_STORAGE_I)
+		do
+			user_oauth_storage := a_user_oauth_storage
+			make (a_api)
+		end
+
+feature {CMS_MODULE} -- Access user oauth storage.
+
+	user_oauth_storage: CMS_USER_OAUTH_STORAGE_I
+
+
+feature -- Access: OAuth2 Gmail
+
+	user_oauth2_gmail_by_id	(a_uid: like {CMS_USER}.id): detachable CMS_USER
+		do
+			Result := user_oauth_storage.user_oauth2_gmail_by_id (a_uid)
+		end
+
+	user_by_oauth2_gmail_token (a_token: READABLE_STRING_32): detachable CMS_USER
+		do
+			Result := user_oauth_storage.user_by_oauth2_gmail_token (a_token)
+		end
+
+
+feature	-- Change: OAuth2 Gmail
+
+	new_user_oauth2_gmail (a_token: READABLE_STRING_32; a_user_profile: READABLE_STRING_32; a_user: CMS_USER)
+			-- Add a new user with oauth2 gmail authentication.
+		require
+			has_id: a_user.has_id
+		do
+			user_oauth_storage.new_user_oauth2_gmail (a_token, a_user_profile, a_user)
+		end
+
+
+	update_user_oauth2_gmail (a_token: READABLE_STRING_32; a_user_profile: READABLE_STRING_32; a_user: CMS_USER)
+			-- Updaate user `a_user' with oauth2 gmail authentication.
+		require
+			has_id: a_user.has_id
+		do
+			user_oauth_storage.update_user_oauth2_gmail (a_token, a_user_profile, a_user)
+		end
+
+end