gecko/layout/reftests/position-dynamic-changes/shrink-wrap.html

<!DOCTYPE html>
<html>
  <body>
    <style>
      #a { border: 1px solid black; position: absolute; }
    </style>
    <div id="a">
      Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod
      tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim
      veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea
      commodo consequat. Duis aute irure dolor in reprehenderit in voluptate
      velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint
      occaecat cupidatat non proident, sunt in culpa qui officia deserunt
      mollit anim id est laborum.
    </div>
  </body>
</html>
Bug 157681 - Part 2: Optimize positioned frame offset changes by moving the frame as opposed to reflowing it in case we know that the size of the frame will not change; r=dbaron This patch adds a change hint to signal that one of the offsets on a frame has been changed. When processing the hint, we do one of the following things based on the position property of the frame. * For static frames, we ignore the offset changes completely, as they will not change the layout. * For relative positioned frames, this patch refactors the nsHTMLReflowState::ComputeRelativeOffsets function so that it can be used from other callers, and it uses that to compute the new relative offsets, and uses the offsets computed previously to compute the new position of the frame. * For absolute positioned frames, we set up a fake parent reflow state object, and then we create a new reflow state object for the frame in question. This setup is similar to what nsFrame::BoxReflow does. Once we have the new reflow state object, we use it to compute the absolute offsets, and then we use the computed offsets to set the new position of the frame. The offset computation is similar to what nsAbsoluteContainingBlock::ReflowAbsoluteFrame does. In some cases where it is possible for the dimensions of the frame to change based on the offset changes, we fall back to a full reflow. 2012-06-05 21:53:48 -07:00			`<!DOCTYPE html>`
			`<html>`
			`<body>`
			`<style>`
			`#a { border: 1px solid black; position: absolute; }`
			`</style>`
			`<div id="a">`
			`Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod`
			`tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim`
			`veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea`
			`commodo consequat. Duis aute irure dolor in reprehenderit in voluptate`
			`velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint`
			`occaecat cupidatat non proident, sunt in culpa qui officia deserunt`
			`mollit anim id est laborum.`
			`</div>`
			`</body>`
			`</html>`