For some reason IE10 craches when document.getElementsByName is called and there is an element with a name attribute but no value. In this case a button had a name attribute set with an empty string as the value.

Right now, checker is being attached to both onblur and onchange.  The result is when the user changes input, and that input loses focus, the checker is being fired twice.  This can cause issues on non-trivial field changes (such as validating a groovy script).  If there is no change, the checker is still called once due to the onblur.

The checker should only be called if the input is changed.

Refactor CSS to make header images relative to the bottom of the header
bar rather than relative to the top.

Enlarge and move Jenkins head image a bit to be flush with the bottom of
the header bar.

Previously, basic auth header was processed from two different servlet
filters in a single filter chain.

In case the 1st filter (ApiTokenFilter) manages to authenticate the
request, the 2nd filter (BasicProcessingFilter) tries to avoid
interpreting the API token as the password and failing authentication
(see BasicProcessingFilter.authenticationIsRequired), but the check
feels rather fragile.

Although I did eventually discover that the original problem (ZD-19640)
was not caused by this, I've already implemented & tested this change,
and this feels like a good work to be wasted, so I'm pushing this in
anyway.

Refrence: ZD-19640