Update navigator.share API to match draft specs.

third_party/WebKit/LayoutTests/webshare/share-arity.html

Index: third_party/WebKit/LayoutTests/webshare/share-arity.html
diff --git a/third_party/WebKit/LayoutTests/webshare/share-arity.html b/third_party/WebKit/LayoutTests/webshare/share-arity.html
index 7ba23f1a94f64938734e8b7a18c3bd8eb4f4caf0..6a8af6860648484a66550075ad0a5214753933a6 100644
--- a/third_party/WebKit/LayoutTests/webshare/share-arity.html
+++ b/third_party/WebKit/LayoutTests/webshare/share-arity.html
@@ -10,12 +10,13 @@ share_test((t, mock) => {
 }, '0 arguments (promise rejection)');
 
 share_test((t, mock) => {
-  return promise_rejects(t, new TypeError(), navigator.share('the title'));
-}, '1 argument (promise rejection)');
+  mock.pushShareResult('the title', 'the message', null);
+  return navigator.share({title: 'the title', text: 'the message', unused: 'unexpected field'});
+}, 'extra ShareData field (extra field ignored)');
 
 share_test((t, mock) => {
   mock.pushShareResult('the title', 'the message', null);
-  return navigator.share('the title', 'the message', 'more than required');
-}, '3 arguments (extra argument ignored)');
+  return navigator.share({title: 'the title', text: 'the message'}, 'more than required');
+}, '2 arguments (extra argument ignored)');
 
 </script>