line-height doesn't work when it is less than font-size

Line-height should work if even if it is less than the font-size, and text overlapping is expected with multiple lines.

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Reproduce the supplied HTML snippet in the renderer and inspect how its font-size, line-height, and multiple lines are laid out. Done means a 10px line-height is honored for 14px text, with overlapping lines permitted as described.

索引モデルが issue の本文から書いたものです。