arrowLeftHover.png is not in PNG format

[GoogleCodeExporter]

In trunk,
com/google/gwt/widgetideas/client/arrowLeftHover.png
is not like its neighbours. 

$ file arrowLeft*
arrowLeftDisabled.png: PNG image data, 14 x 13, 8-bit/color RGB, non-interlaced
arrowLeftHover.png:    PC bitmap data, Windows 3.x format, 14 x 13 x 24
arrowLeft.png:         PNG image data, 14 x 13, 8-bit/color RGB, non-interlaced
arrowLeftPressed.png:  PNG image data, 14 x 13, 8-bit/color RGB, non-interlaced

What's the severity? Some security scanners recognise the MIME type mismatch 
and block the file, assuming there's some trickery going on.

When this file is imported into the release branch of another project and 
published in a zip file, that zip file is blocked from being downloaded.

Original issue reported on code.google.com by [email protected] on 24 Sep 2010 at 4:56