Implement DragEvent and move MouseEvent.dataTransfer

LayoutTests/fast/events/dragevent-constructor-expected.txt

Index: LayoutTests/fast/events/dragevent-constructor-expected.txt
diff --git a/LayoutTests/fast/events/dragevent-constructor-expected.txt b/LayoutTests/fast/events/dragevent-constructor-expected.txt
new file mode 100644
index 0000000000000000000000000000000000000000..152dca11faf9f96f21537d02ade20a9065fa71a2
--- /dev/null
+++ b/LayoutTests/fast/events/dragevent-constructor-expected.txt
@@ -0,0 +1,15 @@
+Tests the constructor of the standard drag event
+
+On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
+
+
+PASS testEvent = new DragEvent('dragstart') did not throw exception.
+PASS testEvent.__proto__ is DragEvent.prototype
+PASS testEvent.dataTransfer is null
+PASS testEvent = new DragEvent('dragstart', { dataTransfer:null }) did not throw exception.
+PASS testEvent.__proto__ is DragEvent.prototype
+PASS testEvent.dataTransfer is null
+PASS successfullyParsed is true
+
+TEST COMPLETE
+