function parseContent(text)
        {
            text = text.toLowerCase();
            var regexResult = text.match(/((?:rgb|hsl)a?\([^)]+\)|#[0-9a-f]{6}|#[0-9a-f]{3})/g) || [];
            for (var c of regexResult) {
                var frequency = this._frequencyMap.get(c) || 0;
                this._frequencyMap.set(c, ++frequency);
            }
            resolve(null);
        }
@param {?string} text
@this {WebInspector.Spectrum.PaletteGenerator}