LayoutTests/fast/block/float/float-clear-with-self-collpasing-box.html

<style>
.spacer {
  margin-top: 50px;
  clear:both;
}

.floater {
  width: 50px;
  height: 50px;
  float: left;
  background-color: blue;
}

.content {
  background-color: green;
  width: 50px;
  height: 50px;
  font-family: Monospace;
  color: transparent;
  font-size: 10px;
}
</style>
<div class=container>
  <div class=floater></div>
  <div class=spacer></div>
  <div class=content></div>
  <div class=spacer></div>
  <div class=content></div>
</div>
<div class=container>
  <div class=floater></div>
  <div class=content>should not overlap</div>
  <div class=spacer></div>
  <div class=content></div>
</div>