public void xml(String xml) {
        if (LogLevel.DEBUG < logConfiguration.logLevel) {
            return;
        }
        printlnInternal(LogLevel.DEBUG, logConfiguration.xmlFormatter.format(xml));
    }
Log a XML string, with level {@link LogLevel#DEBUG} by default.

@param xml the XML string to log
android/android_framework/base/src/main/java/com/elvishew/xlog/Logger.java