Fix #10701, .preventDefault if an inline handler returns false.

Baby unicorns are slapped each time you use inline handlers, so do it sparingly.

src/event.js

@@ -343,9 +343,10 @@ jQuery.event = {
 			if ( handle ) {
 				handle.apply( cur, data );
 			}
+			// Note that this is a bare JS function and not a jQuery handler
 			handle = ontype && cur[ ontype ];
-			if ( handle && jQuery.acceptData( cur ) ) {
-				handle.apply( cur, data );
+			if ( handle && jQuery.acceptData( cur ) && handle.apply( cur, data ) === false ) {
+				event.preventDefault();
 			}
 
 			if ( event.isPropagationStopped() ) {

test/unit/event.js

@@ -2273,6 +2273,18 @@ test("Non DOM element events", function() {
 	jQuery(o).trigger("nonelementobj");
 });
 
+test("inline handler returning false stops default", function() {
+	expect(1);
+
+	var markup = jQuery('<div><a href="#" onclick="return false">x</a></div>');
+	markup.click(function(e) {
+		ok( e.isDefaultPrevented(), "inline handler prevented default");
+		return false;
+	});
+	markup.find("a").click();
+	markup.off("click");
+});
+
 test("window resize", function() {
 	expect(2);