Pad inval rects to compensate for Skia's hairline stroke

third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.h

Index: third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.h
diff --git a/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.h b/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.h
index 3e98bdec89d089ec420f32847ca17490298ca68b..1ee75ac98df84baba25c8f97beae393fc21d8873 100644
--- a/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.h
+++ b/third_party/WebKit/Source/core/layout/compositing/CompositedLayerMapping.h
@@ -501,6 +501,10 @@ class CORE_EXPORT CompositedLayerMapping final : public GraphicsLayerClient {
   // that layer does not appear earlier in the set of layers for this object.
   bool invalidateLayerIfNoPrecedingEntry(size_t);
 
+  // Returns the inval rect adjusted for subpixel accumulation and padded for
+  // safe rasterization.
+  IntRect adjustedInvalRect(const LayoutRect&) const;
+
   PaintLayer& m_owningLayer;
 
   // The hierarchy of layers that is maintained by the CompositedLayerMapping