Grid with hideHeaders:true omits extraneous header border

[Ryanseanlee]

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[amcclain]

Thanks for looking at this - one comment + one question below - let's get it merged in today.

[amcclain]

Looks like xh-ag-grid--hide-headers would be a more consistent with the other classnames here. Agreed we don't need a class for the default "not hidden" case.

[amcclain]

Thanks - let's look together today - right now this is placing an xh-grid-header-- class on the grid itself, which is a bit weird. If we're placing the class on the grid element I would expect it to be an xh-ag-grid-- class like the others. We could then key off of that in an .xh-ag-grid--hide-headers .xh-grid-header override. Or we could look to put the class on the header element itself, in which case we could have it be something like xh-grid-header--hidden - we would just need to see if we can easily check the flag when we are rendering the header.