Adding or changing any of box-shadow, outline, or border-image-outset does not need a layout..

third_party/WebKit/Source/core/layout/LayoutTableRow.h

Index: third_party/WebKit/Source/core/layout/LayoutTableRow.h
diff --git a/third_party/WebKit/Source/core/layout/LayoutTableRow.h b/third_party/WebKit/Source/core/layout/LayoutTableRow.h
index 9f7d669480fd987ba40a2afdd7475ce76e48e34f..053ce1d49eb5837f8b932583522717109a63b557 100644
--- a/third_party/WebKit/Source/core/layout/LayoutTableRow.h
+++ b/third_party/WebKit/Source/core/layout/LayoutTableRow.h
@@ -122,7 +122,7 @@ public:
 
     bool nodeAtPoint(HitTestResult&, const HitTestLocation& locationInContainer, const LayoutPoint& accumulatedOffset, HitTestAction) override;
 
-    void addOverflowFromCell(const LayoutTableCell*);
+    void recomputeOverflow();

[Xianzhu, 2016/04/15 04:59:16]

What's the relationship between 'recomputeOverflow' and
'recalcOverflowAfterStyleChange'?

[rhogan, 2016/04/15 19:34:32]

Nothing really - it's just a refactoring in your table-related part of this
patch. I've renamed it anyway.

[Xianzhu, 2016/04/15 20:48:51]

Now I see why this is named recomputeOverflow/recalculateOverflow instead of
recalcOverflowAfterStyleChange(): this function is called from both
RecalcOverflowAfterStyleChange phase and Layout phase.

If I understood correct, to keep consistency with LayoutBlock, it would be
better to name LayoutTableRow::recomputeOverflow() as
LayoutTableRow::computeOverflow().

 
     const char* name() const override { return "LayoutTableRow"; }
 
@@ -133,6 +133,7 @@ public:
     bool backgroundIsKnownToBeOpaqueInRect(const LayoutRect&) const override { return false; }
 
 private:
+    void addOverflowFromCell(const LayoutTableCell*);
     LayoutObjectChildList* virtualChildren() override { return children(); }
     const LayoutObjectChildList* virtualChildren() const override { return children(); }