[Sanu0074]

сделал так

var gulp = require('gulp'),
    concat = require('gulp-concat'),
    uglify = require('gulp-uglify');

gulp.task('scripts', function () {
    gulp.src([
            "pack-js/jquery.accessible-tabs-1.9.7.min",
            "pack-js/acc.common.js",
            "pack-js/acc.userlocation.js",
            "pack-js/acc.track.js",
            "pack-js/acc.cms.js",
            "pack-js/acc.product.js",
            "pack-js/acc.refinements.js",
            "pack-js/acc.storefinder.js",
            "pack-js/acc.carousel.js",
            "pack-js/acc.autocomplete.js",
            "pack-js/acc.pstrength.js",
            "pack-js/acc.password.js",
            "pack-js/acc.minicart.js",
            "pack-js/acc.pickupinstore.js",
            "pack-js/acc.orderapproval.js",
            "pack-js/acc.langcurrencyselector.js",
            "pack-js/acc.paginationsort.js",
            "pack-js/acc.checkout.js",
            "pack-js/acc.address.js",
            "pack-js/acc.refresh.js",
            "pack-js/acc.stars.js",
            "pack-js/acc.forgotpassword.js",
            "pack-js/acc.productDetail.js",
            "pack-js/acc.producttabs.js",
            "pack-js/acc.variantdetails.js"
        ])
        .pipe(concat('build.common.js'))
        .pipe(uglify())
        .pipe(gulp.dest('js'));
});

gulp.task('default', function() {
    gulp.run('scripts');

    gulp.watch('pack-js/**', function(event) {
        gulp.run('scripts');
    })

});

результат тот же! порядок не сохраняется