Remove dropdown.js as it's not used out-of-the-box

gulpfile.js

@@ -27,7 +27,7 @@ gulp.task('scripts', function () {
     // 'bower_components/bootstrap/js/button.js',
     // 'bower_components/bootstrap/js/carousel.js',
     'bower_components/bootstrap/js/collapse.js',
-    'bower_components/bootstrap/js/dropdown.js',
+    // 'bower_components/bootstrap/js/dropdown.js',
     // 'bower_components/bootstrap/js/modal.js',
     // 'bower_components/bootstrap/js/tooltip.js',
     // 'bower_components/bootstrap/js/popover.js',

js/custom.js

 +function(n){"use strict";function t(){var n=document.createElement("bootstrap"),t={WebkitTransition:"webkitTransitionEnd",MozTransition:"transitionend",OTransition:"oTransitionEnd otransitionend",transition:"transitionend"};for(var i in t)if(void 0!==n.style[i])return{end:t[i]};return!1}n.fn.emulateTransitionEnd=function(t){var i=!1,r=this;n(this).one(n.support.transition.end,function(){i=!0});var o=function(){i||n(r).trigger(n.support.transition.end)};return setTimeout(o,t),this},n(function(){n.support.transition=t()})}(jQuery);
-+function(t){"use strict";var e=function(s,n){this.$element=t(s),this.options=t.extend({},e.DEFAULTS,n),this.transitioning=null,this.options.parent&&(this.$parent=t(this.options.parent)),this.options.toggle&&this.toggle()};e.DEFAULTS={toggle:!0},e.prototype.dimension=function(){var t=this.$element.hasClass("width");return t?"width":"height"},e.prototype.show=function(){if(!this.transitioning&&!this.$element.hasClass("in")){var e=t.Event("show.bs.collapse");if(this.$element.trigger(e),!e.isDefaultPrevented()){var s=this.$parent&&this.$parent.find("> .panel > .in");if(s&&s.length){var n=s.data("bs.collapse");if(n&&n.transitioning)return;s.collapse("hide"),n||s.data("bs.collapse",null)}var i=this.dimension();this.$element.removeClass("collapse").addClass("collapsing")[i](0),this.transitioning=1;var a=function(){this.$element.removeClass("collapsing").addClass("collapse in")[i]("auto"),this.transitioning=0,this.$element.trigger("shown.bs.collapse")};if(!t.support.transition)return a.call(this);var l=t.camelCase(["scroll",i].join("-"));this.$element.one(t.support.transition.end,t.proxy(a,this)).emulateTransitionEnd(350)[i](this.$element[0][l])}}},e.prototype.hide=function(){if(!this.transitioning&&this.$element.hasClass("in")){var e=t.Event("hide.bs.collapse");if(this.$element.trigger(e),!e.isDefaultPrevented()){var s=this.dimension();this.$element[s](this.$element[s]())[0].offsetHeight,this.$element.addClass("collapsing").removeClass("collapse").removeClass("in"),this.transitioning=1;var n=function(){this.transitioning=0,this.$element.trigger("hidden.bs.collapse").removeClass("collapsing").addClass("collapse")};return t.support.transition?void this.$element[s](0).one(t.support.transition.end,t.proxy(n,this)).emulateTransitionEnd(350):n.call(this)}}},e.prototype.toggle=function(){this[this.$element.hasClass("in")?"hide":"show"]()};var s=t.fn.collapse;t.fn.collapse=function(s){return this.each(function(){var n=t(this),i=n.data("bs.collapse"),a=t.extend({},e.DEFAULTS,n.data(),"object"==typeof s&&s);!i&&a.toggle&&"show"==s&&(s=!s),i||n.data("bs.collapse",i=new e(this,a)),"string"==typeof s&&i[s]()})},t.fn.collapse.Constructor=e,t.fn.collapse.noConflict=function(){return t.fn.collapse=s,this},t(document).on("click.bs.collapse.data-api","[data-toggle=collapse]",function(e){var s,n=t(this),i=n.attr("data-target")||e.preventDefault()||(s=n.attr("href"))&&s.replace(/.*(?=#[^\s]+$)/,""),a=t(i),l=a.data("bs.collapse"),o=l?"toggle":n.data(),r=n.attr("data-parent"),h=r&&t(r);l&&l.transitioning||(h&&h.find('[data-toggle=collapse][data-parent="'+r+'"]').not(n).addClass("collapsed"),n[a.hasClass("in")?"addClass":"removeClass"]("collapsed")),a.collapse(o)})}(jQuery);
-+function(o){"use strict";function t(t){o(e).remove(),o(r).each(function(){var e=n(o(this)),r={relatedTarget:this};e.hasClass("open")&&(e.trigger(t=o.Event("hide.bs.dropdown",r)),t.isDefaultPrevented()||e.removeClass("open").trigger("hidden.bs.dropdown",r))})}function n(t){var n=t.attr("data-target");n||(n=t.attr("href"),n=n&&/#[A-Za-z]/.test(n)&&n.replace(/.*(?=#[^\s]*$)/,""));var e=n&&o(n);return e&&e.length?e:t.parent()}var e=".dropdown-backdrop",r="[data-toggle=dropdown]",d=function(t){o(t).on("click.bs.dropdown",this.toggle)};d.prototype.toggle=function(e){var r=o(this);if(!r.is(".disabled, :disabled")){var d=n(r),a=d.hasClass("open");if(t(),!a){"ontouchstart"in document.documentElement&&!d.closest(".navbar-nav").length&&o('<div class="dropdown-backdrop"/>').insertAfter(o(this)).on("click",t);var i={relatedTarget:this};if(d.trigger(e=o.Event("show.bs.dropdown",i)),e.isDefaultPrevented())return;d.toggleClass("open").trigger("shown.bs.dropdown",i),r.focus()}return!1}},d.prototype.keydown=function(t){if(/(38|40|27)/.test(t.keyCode)){var e=o(this);if(t.preventDefault(),t.stopPropagation(),!e.is(".disabled, :disabled")){var d=n(e),a=d.hasClass("open");if(!a||a&&27==t.keyCode)return 27==t.which&&d.find(r).focus(),e.click();var i=" li:not(.divider):visible a",s=d.find("[role=menu]"+i+", [role=listbox]"+i);if(s.length){var p=s.index(s.filter(":focus"));38==t.keyCode&&p>0&&p--,40==t.keyCode&&p<s.length-1&&p++,~p||(p=0),s.eq(p).focus()}}}};var a=o.fn.dropdown;o.fn.dropdown=function(t){return this.each(function(){var n=o(this),e=n.data("bs.dropdown");e||n.data("bs.dropdown",e=new d(this)),"string"==typeof t&&e[t].call(n)})},o.fn.dropdown.Constructor=d,o.fn.dropdown.noConflict=function(){return o.fn.dropdown=a,this},o(document).on("click.bs.dropdown.data-api",t).on("click.bs.dropdown.data-api",".dropdown form",function(o){o.stopPropagation()}).on("click.bs.dropdown.data-api",r,d.prototype.toggle).on("keydown.bs.dropdown.data-api",r+", [role=menu], [role=listbox]",d.prototype.keydown)}(jQuery);
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++function(t){"use strict";var e=function(s,n){this.$element=t(s),this.options=t.extend({},e.DEFAULTS,n),this.transitioning=null,this.options.parent&&(this.$parent=t(this.options.parent)),this.options.toggle&&this.toggle()};e.DEFAULTS={toggle:!0},e.prototype.dimension=function(){var t=this.$element.hasClass("width");return t?"width":"height"},e.prototype.show=function(){if(!this.transitioning&&!this.$element.hasClass("in")){var e=t.Event("show.bs.collapse");if(this.$element.trigger(e),!e.isDefaultPrevented()){var s=this.$parent&&this.$parent.find("> .panel > .in");if(s&&s.length){var n=s.data("bs.collapse");if(n&&n.transitioning)return;s.collapse("hide"),n||s.data("bs.collapse",null)}var i=this.dimension();this.$element.removeClass("collapse").addClass("collapsing")[i](0),this.transitioning=1;var a=function(){this.$element.removeClass("collapsing").addClass("collapse in")[i]("auto"),this.transitioning=0,this.$element.trigger("shown.bs.collapse")};if(!t.support.transition)return a.call(this);var l=t.camelCase(["scroll",i].join("-"));this.$element.one(t.support.transition.end,t.proxy(a,this)).emulateTransitionEnd(350)[i](this.$element[0][l])}}},e.prototype.hide=function(){if(!this.transitioning&&this.$element.hasClass("in")){var e=t.Event("hide.bs.collapse");if(this.$element.trigger(e),!e.isDefaultPrevented()){var s=this.dimension();this.$element[s](this.$element[s]())[0].offsetHeight,this.$element.addClass("collapsing").removeClass("collapse").removeClass("in"),this.transitioning=1;var n=function(){this.transitioning=0,this.$element.trigger("hidden.bs.collapse").removeClass("collapsing").addClass("collapse")};return t.support.transition?void this.$element[s](0).one(t.support.transition.end,t.proxy(n,this)).emulateTransitionEnd(350):n.call(this)}}},e.prototype.toggle=function(){this[this.$element.hasClass("in")?"hide":"show"]()};var s=t.fn.collapse;t.fn.collapse=function(s){return this.each(function(){var n=t(this),i=n.data("bs.collapse"),a=t.extend({},e.DEFAULTS,n.data(),"object"==typeof s&&s);!i&&a.toggle&&"show"==s&&(s=!s),i||n.data("bs.collapse",i=new e(this,a)),"string"==typeof s&&i[s]()})},t.fn.collapse.Constructor=e,t.fn.collapse.noConflict=function(){return t.fn.collapse=s,this},t(document).on("click.bs.collapse.data-api","[data-toggle=collapse]",function(e){var s,n=t(this),i=n.attr("data-target")||e.preventDefault()||(s=n.attr("href"))&&s.replace(/.*(?=#[^\s]+$)/,""),a=t(i),l=a.data("bs.collapse"),o=l?"toggle":n.data(),r=n.attr("data-parent"),h=r&&t(r);l&&l.transitioning||(h&&h.find('[data-toggle=collapse][data-parent="'+r+'"]').not(n).addClass("collapsed"),n[a.hasClass("in")?"addClass":"removeClass"]("collapsed")),a.collapse(o)})}(jQuery);
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