handlers: HandlerPageEdit: Add transaction rollback on exception

handlers/handlerpageedit.cpp

@@ -115,6 +115,7 @@ Response HandlerPageEdit::handleRequest(PageDao &pageDao, std::string pagename,
 			}
 			catch(const DatabaseException &e)
 			{
+				this->database->rollbackTransaction();
 				Logger::debug() << "Error saving revision: " << e.what();
 				return errorResponse("Database error", "A database error occured while trying to save this revision");
 			}