Ref #14180, let focusin/out work on non-element targets.

src/event.js

@@ -728,7 +728,7 @@ if ( !support.focusinBubbles ) {
 
 		jQuery.event.special[ fix ] = {
 			setup: function() {
-				var doc = this.ownerDocument,
+				var doc = this.ownerDocument || this,
 					attaches = data_priv.access( doc, fix );
 
 				if ( !attaches ) {
@@ -737,7 +737,7 @@ if ( !support.focusinBubbles ) {
 				data_priv.access( doc, fix, ( attaches || 0 ) + 1 );
 			},
 			teardown: function() {
-				var doc = this.ownerDocument,
+				var doc = this.ownerDocument || this,
 					attaches = data_priv.access( doc, fix ) - 1;
 
 				if ( !attaches ) {

test/unit/event.js

@@ -2374,6 +2374,19 @@ test("fixHooks extensions", function() {
 	jQuery.event.fixHooks.click = saved;
 });
 
+test( "focusin using non-element targets", function() {
+	expect( 2 );
+
+	jQuery( document ).on( "focusin", function( e ) {
+		ok( e.type === "focusin", "got a focusin event on a document" );
+	}).trigger( "focusin" ).off( "focusin" );
+
+	jQuery( window ).on( "focusin", function( e ) {
+		ok( e.type === "focusin", "got a focusin event on a window" );
+	}).trigger( "focusin" ).off( "focusin" );
+
+});
+
 testIframeWithCallback( "focusin from an iframe", "event/focusinCrossFrame.html", function( frameDoc ) {
 	expect(1);