Button_mouse.html dropdown test failure on IE6

[bill]

At least on my machine, I get failures in Button_mouse.html on IE6, both in [21297] (when you introduced the test) and in trunk:

On [21297]:

GROUP "submit" has 7 tests to run
_AssertFailure: [object Error]: assertEqual() failed: expected DropDown but got Plain with hint: Plain name 
[ Error: assertEqual() failed: expected DropDown but got Plain with hint: Plain name ]
ERROR IN: function()
FAILED test: plain 2109 ms
_AssertFailure: [object Error]: assertEqual() failed: expected DropDown but got Combo with hint: Combo name 
[ Error: assertEqual() failed: expected DropDown but got Combo with hint: Combo name ]
ERROR IN: function()
FAILED test: combo left 2110 ms
PASSED test: combo right 2110 ms
_AssertFailure: [object Error]: assertEqual() failed: expected DropDown but got with hint: Combo Arrow name 
[ Error: assertEqual() failed: expected DropDown but got with hint: Combo Arrow name ]
ERROR IN: function()
FAILED test: combo menu 2609 ms

On trunk:

GROUP "submit" has 7 tests to run
PASSED test: plain 2110 ms
PASSED test: combo left 2109 ms
PASSED test: combo right 2109 ms
PASSED test: combo menu 2609 ms
_AssertFailure: [object Error]: assertEqual() failed: expected INIT but got DropDown with hint: DropDown name 
[ Error: assertEqual() failed: expected INIT but got DropDown with hint: DropDown name ]
ERROR IN: function()
FAILED test: drop down 2110 ms

Fails consistently when running Button_mouse.html standalone. Also fails via runTests.html.

[Douglas Hays]

(In [22830]) Fixes #11684. Workaround an apparent IE6 problem with updating a textbox (hidden by scrolling) value from an onsubmit handler.