Unnecessary .fill child for .topbar?

Created by: karthikv

As per a comment in patterns.less, the .fill element is in place because "overflow visible is not honored by IE when filter is present" (https://github.com/twitter/bootstrap/blob/master/lib/patterns.less#L19). This comment no longer seems to apply, though, as no filters remain in both .topbar and .fill. Consequently, can this extra element be removed by applying its styles directly to .topbar? The code I'm referring to is included below for ease of reference:

.topbar {
  height: 40px;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 10000;
  overflow: visible;

  // gradient is applied to it's own element because overflow visible is not honored by ie when filter is present
  .fill {
    background:#222;
    #gradient > .vertical(#333, #222);
    @shadow: 0 1px 3px rgba(0,0,0,.25), inset 0 -1px 0 rgba(0,0,0,.1);
    .box-shadow(@shadow);
  }

  // [omitted code]
}