generateInnerHTML = function generateInnerHTML(cssPrefix, height) {
    var logoHeight = height * _LOGO_SCALE;
    var svgString = generateVRIconString(cssPrefix, logoHeight) + generateNoVRIconString(cssPrefix, logoHeight);

    return '<button class="' + cssPrefix + '-button">\n          <div class="' + cssPrefix + '-title"></div>\n          <div class="' + cssPrefix + '-logo" >' + svgString + '</div>\n        </button>';
}
Generate the innerHTML for the button

@return {string} html of the button as string
@param {string} cssPrefix
@param {Number} height
@private