Merge 142659

Source/WebCore/rendering/RenderBlockLineLayout.cpp

Index: Source/WebCore/rendering/RenderBlockLineLayout.cpp
===================================================================
--- Source/WebCore/rendering/RenderBlockLineLayout.cpp	(revision 143750)
+++ Source/WebCore/rendering/RenderBlockLineLayout.cpp	(working copy)
@@ -2281,8 +2281,8 @@
             }
         } else if (object->isFloating()) {
             // The top margin edge of a self-collapsing block that clears a float intrudes up into it by the height of the margin,
-            // so in order to place this child float at the top content edge of the self-collapsing block add the margin back in before placement.
-            LayoutUnit marginOffset = (m_block->isSelfCollapsingBlock() && m_block->style()->clear() && m_block->getClearDelta(m_block, LayoutUnit())) ? m_block->collapsedMarginBeforeForChild(m_block) : LayoutUnit();
+            // so in order to place this first child float at the top content edge of the self-collapsing block add the margin back in before placement.
+            LayoutUnit marginOffset = (!object->previousSibling() && m_block->isSelfCollapsingBlock() && m_block->style()->clear() && m_block->getClearDelta(m_block, LayoutUnit())) ? m_block->collapsedMarginBeforeForChild(m_block) : LayoutUnit();
             LayoutUnit oldLogicalHeight = m_block->logicalHeight();
             m_block->setLogicalHeight(oldLogicalHeight + marginOffset);
             m_block->positionNewFloatOnLine(m_block->insertFloatingObject(toRenderBox(object)), lastFloatFromPreviousLine, lineInfo, width);