Fixed mouseenter/mouseleave event firing order.

LayoutTests/fast/events/mouseenter-mouseleave-on-drag-expected.txt

Index: LayoutTests/fast/events/mouseenter-mouseleave-on-drag-expected.txt
diff --git a/LayoutTests/fast/events/mouseenter-mouseleave-on-drag-expected.txt b/LayoutTests/fast/events/mouseenter-mouseleave-on-drag-expected.txt
new file mode 100644
index 0000000000000000000000000000000000000000..bb451b67a07c1726e705f33a1e590923da1cc8d7
--- /dev/null
+++ b/LayoutTests/fast/events/mouseenter-mouseleave-on-drag-expected.txt
@@ -0,0 +1,19 @@
+Verifies that dragging mouse in/out of an element doesn't fire redundant mouseenter or mouseleave events (crbug.com/470258)
+
+On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
+
+
+outer received mouseenter
+PASS wasInside['outer'] is false
+outer received mousedown
+inner received mouseenter
+PASS wasInside['inner'] is false
+inner received mouseleave
+PASS wasInside['inner'] is true
+outer received mouseup
+outer received mouseleave
+PASS wasInside['outer'] is true
+PASS successfullyParsed is true
+
+TEST COMPLETE
+