Fix #14180. Allow cross-frame use of focusin/out. Close gh-1369.

(cherry picked from commit 6d5dfa0eda2c19e8838930fafff83b596654eca2)
Manually edited for conflicts.

src/event.js

@@ -892,22 +892,29 @@ if ( !support.changeBubbles ) {
 if ( !support.focusinBubbles ) {
 	jQuery.each({ focus: "focusin", blur: "focusout" }, function( orig, fix ) {
 
-		// Attach a single capturing handler while someone wants focusin/focusout
-		var attaches = 0,
-			handler = function( event ) {
+		// Attach a single capturing handler on the document while someone wants focusin/focusout
+		var handler = function( event ) {
 				jQuery.event.simulate( fix, event.target, jQuery.event.fix( event ), true );
 			};
 
 		jQuery.event.special[ fix ] = {
 			setup: function() {
-				if ( attaches++ === 0 ) {
-					document.addEventListener( orig, handler, true );
+				var doc = this.ownerDocument,
+					attaches = jQuery._data( doc, "focusCount" );
+
+				if ( !attaches ) {
+					doc.addEventListener( orig, handler, true );
 				}
+				jQuery._data( doc, "focusCount", ( attaches || 0 ) + 1 );
 			},
 			teardown: function() {
-				if ( --attaches === 0 ) {
-					document.removeEventListener( orig, handler, true );
+				var doc = this.ownerDocument,
+					attaches = jQuery._data( doc, "focusCount" ) - 1;
+
+				if ( !attaches ) {
+					doc.removeEventListener( orig, handler, true );
 				}
+				jQuery._data( doc, "focusCount", attaches );
 			}
 		};
 	});

test/data/event/focusinCrossFrame.html

+<!doctype html>
+<html>
+<head>
+	<meta http-equiv="Content-type" content="text/html; charset=utf-8">
+	<title>focusin event cross-frame (#14180)</title>
+
+	<script src="../../jquery.js"></script>
+</head>
+<body>
+	<input type="text" id="frame-input" />
+	<script>
+		// Call parent when this frame is fully loaded, it will mess with #frame-input
+		jQuery( window ).one( "load", function() {
+			window.parent.iframeCallback( document );
+		});
+	</script>
+</body>
+</html>

test/unit/event.js

@@ -2507,6 +2507,33 @@ test("fixHooks extensions", function() {
 	jQuery.event.fixHooks.click = saved;
 });
 
+testIframeWithCallback( "focusin from an iframe", "event/focusinCrossFrame.html", function( frameDoc ) {
+	expect(1);
+
+	var input = jQuery( frameDoc ).find( "#frame-input" );
+
+	// Create a focusin handler on the parent; shouldn't affect the iframe's fate
+	jQuery ( "body" ).on( "focusin.iframeTest", function() {
+		ok( false, "fired a focusin event in the parent document" );
+	});
+
+	input.on( "focusin", function() {
+		ok( true, "fired a focusin event in the iframe" );
+	});
+
+	// Avoid a native event; Chrome can't force focus to another frame
+	input.trigger( "focusin" );
+
+	// Must manually remove handler to avoid leaks in our data store
+	input.remove();
+
+	// Be sure it was removed; nothing should happen
+	input.trigger( "focusin" );
+
+	// Remove body handler manually since it's outside the fixture
+	jQuery( "body" ).off( "focusin.iframeTest" );
+});
+
 testIframeWithCallback( "jQuery.ready promise", "event/promiseReady.html", function( isOk ) {
 	expect(1);
 	ok( isOk, "$.when( $.ready ) works" );