RenderLayer::shouldBeOverflowOnly() decides if a layer is an overflow-only layer (just used for clipping, and not a parent of other RenderLayers). It currently does not look for transforms, which create stacking context and behave like position:relative. I think it should.
<body style="margin:0"> <div style="position:absolute; background-color:red; z-index:0; left: 50px; top:50px; width:100px;height:100px"></div> <div style="overflow:auto; -webkit-transform: scale(0.5); background-color:green; z-index:0; width:200px; height:200px"></div>
I think that might be a valid test case, but not 100% sure. Would have to think about it some more.
Created attachment 22194 [details] Testcase
Created attachment 22195 [details] Patch
Comment on attachment 22195 [details] Patch r=me, but need a ChangeLog and the test case included in LayoutTests to land.
Created attachment 22200 [details] Final patch with changelog and testcase
Comment on attachment 22200 [details] Final patch with changelog and testcase Transferring r= from hyatt
Committed r35100
Committed by dino in r35100