From the discussion in https://crrev.com/c/1173725:

Xiaocheng:
Checking emptiness of paint fragment range doesn't work, as a LayoutInline may be partially culled. Found in the following tests:

NEEDBUG css3/selectors3/html/css3-modsel-179a.html [ Failure ]
NEEDBUG css3/selectors3/html/css3-modsel-38.html [ Failure ]
NEEDBUG css3/selectors3/xhtml/css3-modsel-179a.xml [ Failure ]
NEEDBUG css3/selectors3/xhtml/css3-modsel-38.xml [ Failure ]
NEEDBUG css3/selectors3/xml/css3-modsel-179a.xml [ Failure ]
NEEDBUG css3/selectors3/xml/css3-modsel-38.xml [ Failure ]
NEEDBUG fast/box-shadow/basic-shadows.html [ Failure ]
NEEDBUG fast/encoding/utf-16-big-endian.html [ Failure ]
NEEDBUG fast/encoding/utf-16-little-endian.html [ Failure ]
NEEDBUG fast/selectors/038.html [ Failure ]
NEEDBUG images/image-map-anchor-children.html [ Failure ]
NEEDBUG virtual/gpu-rasterization/images/image-map-anchor-children.html [ Failure ]

yosin:
Yes, for ::first-line, <span> for other than ::first-line are culled.

::first-line css3/selectors3/html/css3-modsel-179a.html [ Failure ]
::first-line css3/selectors3/html/css3-modsel-38.html [ Failure ]
::first-line css3/selectors3/xhtml/css3-modsel-179a.xml [ Failure ]
::first-line css3/selectors3/xhtml/css3-modsel-38.xml [ Failure ]
::first-line css3/selectors3/xml/css3-modsel-179a.xml [ Failure ]
::first-line css3/selectors3/xml/css3-modsel-38.xml [ Failure ]
::first-line  fast/box-shadow/basic-shadows.html [ Failure ]
coordinate fast/encoding/utf-16-big-endian.html [ Failure ]
coordinate fast/encoding/utf-16-little-endian.html [ Failure ]
::first-line fast/selectors/038.html [ Failure ]
extra images/image-map-anchor-children.html [ Failure ]

# ::first-line
NGPaintFragment::InlineFragmentsFor() returns a fragment for first line.
<span> is used for specifying color. <span> for rest of lines are culled and not appeared in fragment tree.

# coordinate
paint fragment version returns integer coordinate but physical fragment version returns float coordinate

# extra

LayoutInlineCollector() returns fragments for <map> and <br>
InlineFragmentsFor() returns <map>
Layout tree dump of InlineFragmentsFor() matches legacy layout tree dump.