void updateDetectedCharset(CharsetDetectionResult currentDetectionResult) {
        if (detectionResult.isFound() && needPragma != null && !(needPragma && !gotPragma)) {
            currentDetectionResult.setCharset(detectionResult.getCharset());
        }
    }
A class to process the attributes of an HTML meta tag in order to extract a character set.
The user should repeatedly call {@link #processAttribute} on each attributes of the tag,
then update its current detection result with
{@link #updateDetectedCharset(CharsetDetectionResult)}
<p>
The algorithm implemented is meant to match the one described by the W3C here:
https://html.spec.whatwg.org/multipage/parsing.html#prescan-a-byte-stream-to-determine-its-encoding
tika-parsers/tika-parsers-standard/tika-parsers-standard-modules/tika-parser-html-module/src/main/java/org/apache/tika/parser/html/charsetdetector/MetaProcessor.java