diff --git a/wp-includes/js/customize-models.js b/wp-includes/js/customize-models.js
index 3c8001c4b1..5fa62aeecc 100644
--- a/wp-includes/js/customize-models.js
+++ b/wp-includes/js/customize-models.js
@@ -1,4 +1,4 @@
-/* globals _wpCustomizeHeader */
+/* globals _wpCustomizeHeader, _ */
 (function( $, wp ) {
 	var api = wp.customize;
 	api.HeaderTool = {};
@@ -142,7 +142,7 @@
 			}
 
 			// Overridable by an extending class
-			if (!this.data) {
+			if (typeof this.data === 'undefined') {
 				this.data = _wpCustomizeHeader.uploads;
 			}
 
diff --git a/wp-includes/js/customize-models.min.js b/wp-includes/js/customize-models.min.js
index dd7a1145fe..f7565c4666 100644
--- a/wp-includes/js/customize-models.min.js
+++ b/wp-includes/js/customize-models.min.js
@@ -1 +1 @@
-!function(a,b){var c=b.customize;c.HeaderTool={},c.HeaderTool.ImageModel=Backbone.Model.extend({defaults:function(){return{header:{attachment_id:0,url:"",timestamp:_.now(),thumbnail_url:""},choice:"",selected:!1,random:!1}},initialize:function(){this.on("hide",this.hide,this)},hide:function(){this.set("choice",""),c("header_image").set("remove-header"),c("header_image_data").set("remove-header")},destroy:function(){var a=this.get("header"),d=c.HeaderTool.currentHeader.get("header").attachment_id;d&&a.attachment_id===d&&c.HeaderTool.currentHeader.trigger("hide"),b.ajax.post("custom-header-remove",{nonce:_wpCustomizeHeader.nonces.remove,wp_customize:"on",theme:c.settings.theme.stylesheet,attachment_id:a.attachment_id}),this.trigger("destroy",this,this.collection)},save:function(){this.get("random")?(c("header_image").set(this.get("header").random),c("header_image_data").set(this.get("header").random)):this.get("header").defaultName?(c("header_image").set(this.get("header").url),c("header_image_data").set(this.get("header").defaultName)):(c("header_image").set(this.get("header").url),c("header_image_data").set(this.get("header"))),c.HeaderTool.combinedList.trigger("control:setImage",this)},importImage:function(){var a=this.get("header");void 0!==a.attachment_id&&b.ajax.post("custom-header-add",{nonce:_wpCustomizeHeader.nonces.add,wp_customize:"on",theme:c.settings.theme.stylesheet,attachment_id:a.attachment_id})},shouldBeCropped:function(){return this.get("themeFlexWidth")===!0&&this.get("themeFlexHeight")===!0?!1:this.get("themeFlexWidth")===!0&&this.get("themeHeight")===this.get("imageHeight")?!1:this.get("themeFlexHeight")===!0&&this.get("themeWidth")===this.get("imageWidth")?!1:this.get("themeWidth")===this.get("imageWidth")&&this.get("themeHeight")===this.get("imageHeight")?!1:!0}}),c.HeaderTool.ChoiceList=Backbone.Collection.extend({model:c.HeaderTool.ImageModel,comparator:function(a){return-a.get("header").timestamp},initialize:function(){var a=c.HeaderTool.currentHeader.get("choice").replace(/^https?:\/\//,""),b=this.isRandomChoice(c.get().header_image);this.type||(this.type="uploaded"),this.data||(this.data=_wpCustomizeHeader.uploads),b&&(a=c.get().header_image),this.on("control:setImage",this.setImage,this),this.on("control:removeImage",this.removeImage,this),this.on("add",this.maybeAddRandomChoice,this),_.each(this.data,function(b,c){b.attachment_id||(b.defaultName=c),"undefined"==typeof b.timestamp&&(b.timestamp=0),this.add({header:b,choice:b.url.split("/").pop(),selected:a===b.url.replace(/^https?:\/\//,"")},{silent:!0})},this),this.size()>0&&this.addRandomChoice(a)},maybeAddRandomChoice:function(){1===this.size()&&this.addRandomChoice()},addRandomChoice:function(a){var b=RegExp(this.type).test(a),c="random-"+this.type+"-image";this.add({header:{timestamp:0,random:c,width:245,height:41},choice:c,random:!0,selected:b})},isRandomChoice:function(a){return/^random-(uploaded|default)-image$/.test(a)},shouldHideTitle:function(){return this.size()<2},setImage:function(a){this.each(function(a){a.set("selected",!1)}),a&&a.set("selected",!0)},removeImage:function(){this.each(function(a){a.set("selected",!1)})}}),c.HeaderTool.DefaultsList=c.HeaderTool.ChoiceList.extend({initialize:function(){this.type="default",this.data=_wpCustomizeHeader.defaults,c.HeaderTool.ChoiceList.prototype.initialize.apply(this)}})}(jQuery,window.wp);
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+!function(a,b){var c=b.customize;c.HeaderTool={},c.HeaderTool.ImageModel=Backbone.Model.extend({defaults:function(){return{header:{attachment_id:0,url:"",timestamp:_.now(),thumbnail_url:""},choice:"",selected:!1,random:!1}},initialize:function(){this.on("hide",this.hide,this)},hide:function(){this.set("choice",""),c("header_image").set("remove-header"),c("header_image_data").set("remove-header")},destroy:function(){var a=this.get("header"),d=c.HeaderTool.currentHeader.get("header").attachment_id;d&&a.attachment_id===d&&c.HeaderTool.currentHeader.trigger("hide"),b.ajax.post("custom-header-remove",{nonce:_wpCustomizeHeader.nonces.remove,wp_customize:"on",theme:c.settings.theme.stylesheet,attachment_id:a.attachment_id}),this.trigger("destroy",this,this.collection)},save:function(){this.get("random")?(c("header_image").set(this.get("header").random),c("header_image_data").set(this.get("header").random)):this.get("header").defaultName?(c("header_image").set(this.get("header").url),c("header_image_data").set(this.get("header").defaultName)):(c("header_image").set(this.get("header").url),c("header_image_data").set(this.get("header"))),c.HeaderTool.combinedList.trigger("control:setImage",this)},importImage:function(){var a=this.get("header");void 0!==a.attachment_id&&b.ajax.post("custom-header-add",{nonce:_wpCustomizeHeader.nonces.add,wp_customize:"on",theme:c.settings.theme.stylesheet,attachment_id:a.attachment_id})},shouldBeCropped:function(){return this.get("themeFlexWidth")===!0&&this.get("themeFlexHeight")===!0?!1:this.get("themeFlexWidth")===!0&&this.get("themeHeight")===this.get("imageHeight")?!1:this.get("themeFlexHeight")===!0&&this.get("themeWidth")===this.get("imageWidth")?!1:this.get("themeWidth")===this.get("imageWidth")&&this.get("themeHeight")===this.get("imageHeight")?!1:!0}}),c.HeaderTool.ChoiceList=Backbone.Collection.extend({model:c.HeaderTool.ImageModel,comparator:function(a){return-a.get("header").timestamp},initialize:function(){var a=c.HeaderTool.currentHeader.get("choice").replace(/^https?:\/\//,""),b=this.isRandomChoice(c.get().header_image);this.type||(this.type="uploaded"),"undefined"==typeof this.data&&(this.data=_wpCustomizeHeader.uploads),b&&(a=c.get().header_image),this.on("control:setImage",this.setImage,this),this.on("control:removeImage",this.removeImage,this),this.on("add",this.maybeAddRandomChoice,this),_.each(this.data,function(b,c){b.attachment_id||(b.defaultName=c),"undefined"==typeof b.timestamp&&(b.timestamp=0),this.add({header:b,choice:b.url.split("/").pop(),selected:a===b.url.replace(/^https?:\/\//,"")},{silent:!0})},this),this.size()>0&&this.addRandomChoice(a)},maybeAddRandomChoice:function(){1===this.size()&&this.addRandomChoice()},addRandomChoice:function(a){var b=RegExp(this.type).test(a),c="random-"+this.type+"-image";this.add({header:{timestamp:0,random:c,width:245,height:41},choice:c,random:!0,selected:b})},isRandomChoice:function(a){return/^random-(uploaded|default)-image$/.test(a)},shouldHideTitle:function(){return this.size()<2},setImage:function(a){this.each(function(a){a.set("selected",!1)}),a&&a.set("selected",!0)},removeImage:function(){this.each(function(a){a.set("selected",!1)})}}),c.HeaderTool.DefaultsList=c.HeaderTool.ChoiceList.extend({initialize:function(){this.type="default",this.data=_wpCustomizeHeader.defaults,c.HeaderTool.ChoiceList.prototype.initialize.apply(this)}})}(jQuery,window.wp);
\ No newline at end of file