=COUNTIFS(ROUNDUP(MONTH('sheet-label'!B2)/3),1)

=COUNTIFS(ROUNDUP(MONTH('sheet-label'!B1:B50)/3),1)

function countQuarterByYear(date, quarter, year) {

  var counter = 0;
  var arrayLength = date.length;
  var dateYear;
  var dateQuarter;
  var dateTemp;

  for(var i = 0; i < arrayLength; i++) {

    dateTemp = date[i];

    dateYear = dateTemp.getYear;

    dateQuarter = dateTemp.getMonth;
    dateQuarter = Math.ceil(dateQuarter/3);


    if ((dateYear == year) && (dateQuarter == quarter)){
   counter++;
  }

  }
  return counter;

}

function test() {
  countQuarterByYear(["2/7/2016", "8/5/2015"], 2, 2015);

}