Selection: Remove client callback for unit conversion.

Now clients provide a unit conversion context and libcss provides
code to perform unit conversion.

This reduces the amount of common code that clients have to write.

2 files changed, 140 insertions, 191 deletions

diff --git a/test/data/select/tests1.dat b/test/data/select/tests1.dat
index eaf37d7..295ab2e 100644
--- a/test/data/select/tests1.dat
+++ b/test/data/select/tests1.dat
@@ -59,7 +59,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -173,7 +173,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -291,7 +291,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -410,7 +410,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -529,7 +529,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -648,7 +648,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -757,7 +757,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -867,7 +867,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -977,7 +977,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -1086,7 +1086,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -1200,7 +1200,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -1314,7 +1314,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -1429,7 +1429,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -1547,7 +1547,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -1664,7 +1664,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -1787,7 +1787,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -1910,7 +1910,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -2033,7 +2033,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -2160,7 +2160,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -2286,7 +2286,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -2410,7 +2410,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -2533,7 +2533,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -2656,7 +2656,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -2779,7 +2779,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -2902,7 +2902,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -3025,7 +3025,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -3148,7 +3148,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -3271,7 +3271,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -3394,7 +3394,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -3517,7 +3517,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -3640,7 +3640,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 10.600pt
+font-size: 13.342px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -3763,7 +3763,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 14.391pt
+font-size: 19.187px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -3886,7 +3886,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 24pt
+font-size: 32px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -4009,7 +4009,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 18pt
+font-size: 24px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -4132,7 +4132,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 13.500pt
+font-size: 18px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -4255,7 +4255,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -4378,7 +4378,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 9.750pt
+font-size: 13px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -4501,7 +4501,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 7.500pt
+font-size: 10px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -4624,7 +4624,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 6.750pt
+font-size: 9px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -4870,7 +4870,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -4986,7 +4986,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -5102,7 +5102,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -5218,7 +5218,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -5331,7 +5331,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -5445,7 +5445,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -5559,7 +5559,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -5673,7 +5673,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -5783,7 +5783,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -5894,7 +5894,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -6004,7 +6004,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -6114,7 +6114,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -6224,7 +6224,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -6334,7 +6334,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -6444,7 +6444,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -6556,7 +6556,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -6666,7 +6666,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -6776,7 +6776,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -6887,7 +6887,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -6997,7 +6997,7 @@ flex-shrink: 3.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -7107,7 +7107,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -7217,7 +7217,7 @@ flex-shrink: 0.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -7327,7 +7327,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -7437,7 +7437,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -7547,7 +7547,7 @@ flex-shrink: 0.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -7657,7 +7657,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -7766,7 +7766,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -7875,7 +7875,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -7984,7 +7984,7 @@ flex-shrink: 30.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -8095,7 +8095,7 @@ flex-shrink: 3.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -8206,7 +8206,7 @@ flex-shrink: 3.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -8315,7 +8315,7 @@ flex-shrink: 0.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -8426,7 +8426,7 @@ flex-shrink: 0.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -8537,7 +8537,7 @@ flex-shrink: 3.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -8648,7 +8648,7 @@ flex-shrink: 3.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -8757,7 +8757,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -8866,7 +8866,7 @@ flex-shrink: 1.000
 flex-wrap: wrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -8975,7 +8975,7 @@ flex-shrink: 1.000
 flex-wrap: wrap-reverse
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -9084,7 +9084,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -9193,7 +9193,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -9302,7 +9302,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -9411,7 +9411,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -9520,7 +9520,7 @@ flex-shrink: 1.000
 flex-wrap: wrap-reverse
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -9631,7 +9631,7 @@ flex-shrink: 1.000
 flex-wrap: wrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -9742,7 +9742,7 @@ flex-shrink: 1.000
 flex-wrap: wrap-reverse
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -9851,7 +9851,7 @@ flex-shrink: 0.899
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -9960,7 +9960,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -10069,7 +10069,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -10178,7 +10178,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -10287,7 +10287,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -10396,7 +10396,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -10505,7 +10505,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -10616,7 +10616,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -10727,7 +10727,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -10836,7 +10836,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -10945,7 +10945,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -11054,7 +11054,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -11165,7 +11165,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -11274,7 +11274,7 @@ flex-shrink: 3.780
 flex-wrap: wrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -11385,7 +11385,7 @@ flex-shrink: 3.780
 flex-wrap: wrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -11494,7 +11494,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -11603,7 +11603,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -11712,7 +11712,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -11821,7 +11821,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -11930,7 +11930,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -12039,7 +12039,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -12148,7 +12148,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -12257,7 +12257,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -12366,7 +12366,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -12475,7 +12475,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -12584,7 +12584,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -12693,7 +12693,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -12802,7 +12802,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -12911,7 +12911,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -13020,7 +13020,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -13129,7 +13129,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -13238,7 +13238,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -13347,7 +13347,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -13456,7 +13456,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -13565,7 +13565,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -13674,7 +13674,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -13783,7 +13783,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -13892,7 +13892,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
@@ -14020,7 +14020,7 @@ flex-shrink: 1.000
 flex-wrap: nowrap
 float: none
 font-family: sans-serif
-font-size: 12pt
+font-size: 16px
 font-style: normal
 font-variant: normal
 font-weight: normal
diff --git a/test/select.c b/test/select.c
index 33f31dd..a3319fe 100644
--- a/test/select.c
+++ b/test/select.c
@@ -159,13 +159,15 @@ static css_error node_presentational_hint(void *pw, void *node,
 		uint32_t *nhints, css_hint **hints);
 static css_error ua_default_for_property(void *pw, uint32_t property,
 		css_hint *hints);
-static css_error compute_font_size(void *pw, const css_hint *parent,
-		css_hint *size);
 static css_error set_libcss_node_data(void *pw, void *n,
 		void *libcss_node_data);
 static css_error get_libcss_node_data(void *pw, void *n,
 		void **libcss_node_data);
 
+static css_unit_len_ctx unit_len_ctx = {
+	.font_size_default = 16 * (1 << CSS_RADIX_POINT),
+};
+
 static css_select_handler select_handler = {
 	CSS_SELECT_HANDLER_VERSION_1,
 
@@ -203,9 +205,9 @@ static css_select_handler select_handler = {
 	node_is_lang,
 	node_presentational_hint,
 	ua_default_for_property,
-	compute_font_size,
+
 	set_libcss_node_data,
-	get_libcss_node_data
+	get_libcss_node_data,
 };
 
 static css_error resolve_url(void *pw,
@@ -798,7 +800,12 @@ static void run_test_select_tree(css_select_ctx *select,
 	css_select_results *sr;
 	struct node *n = NULL;
 
-	assert(css_select_style(select, node, &ctx->media, NULL,
+	if (node->parent == NULL) {
+		unit_len_ctx.root_style = NULL;
+	}
+
+
+	assert(css_select_style(select, node, &unit_len_ctx, &ctx->media, NULL,
 			&select_handler, ctx, &sr) == CSS_OK);
 
 	if (node->parent != NULL) {
@@ -806,7 +813,7 @@ static void run_test_select_tree(css_select_ctx *select,
 		assert(css_computed_style_compose(
 				node->parent->sr->styles[ctx->pseudo_element],
 				sr->styles[ctx->pseudo_element],
-				compute_font_size, NULL,
+				&unit_len_ctx,
 				&composed) == CSS_OK);
 		css_computed_style_destroy(sr->styles[ctx->pseudo_element]);
 		sr->styles[ctx->pseudo_element] = composed;
@@ -819,6 +826,10 @@ static void run_test_select_tree(css_select_ctx *select,
 				buf, buflen);
 	}
 
+	if (node->parent == NULL) {
+		unit_len_ctx.root_style = node->sr->styles[ctx->pseudo_element];
+	}
+
 	for (n = node->children; n != NULL; n = n->next) {
 		run_test_select_tree(select, n, ctx, buf, buflen);
 	}
@@ -1639,68 +1650,6 @@ css_error ua_default_for_property(void *pw, uint32_t property, css_hint *hint)
 	return CSS_OK;
 }
 
-css_error compute_font_size(void *pw, const css_hint *parent, css_hint *size)
-{
-	static css_hint_length sizes[] = {
-		{ FLTTOFIX(6.75), CSS_UNIT_PT },
-		{ FLTTOFIX(7.50), CSS_UNIT_PT },
-		{ FLTTOFIX(9.75), CSS_UNIT_PT },
-		{ FLTTOFIX(12.0), CSS_UNIT_PT },
-		{ FLTTOFIX(13.5), CSS_UNIT_PT },
-		{ FLTTOFIX(18.0), CSS_UNIT_PT },
-		{ FLTTOFIX(24.0), CSS_UNIT_PT }
-	};
-	const css_hint_length *parent_size;
-
-	UNUSED(pw);
-
-	/* Grab parent size, defaulting to medium if none */
-	if (parent == NULL) {
-		parent_size = &sizes[CSS_FONT_SIZE_MEDIUM - 1];
-	} else {
-		assert(parent->status == CSS_FONT_SIZE_DIMENSION);
-		assert(parent->data.length.unit != CSS_UNIT_EM);
-		assert(parent->data.length.unit != CSS_UNIT_EX);
-		parent_size = &parent->data.length;
-	}
-
-	assert(size->status != CSS_FONT_SIZE_INHERIT);
-
-	if (size->status < CSS_FONT_SIZE_LARGER) {
-		/* Keyword -- simple */
-		size->data.length = sizes[size->status - 1];
-	} else if (size->status == CSS_FONT_SIZE_LARGER) {
-		/** \todo Step within table, if appropriate */
-		size->data.length.value =
-				FMUL(parent_size->value, FLTTOFIX(1.2));
-		size->data.length.unit = parent_size->unit;
-	} else if (size->status == CSS_FONT_SIZE_SMALLER) {
-		/** \todo Step within table, if appropriate */
-		size->data.length.value =
-				FDIV(parent_size->value, FLTTOFIX(1.2));
-		size->data.length.unit = parent_size->unit;
-	} else if (size->data.length.unit == CSS_UNIT_EM ||
-			size->data.length.unit == CSS_UNIT_EX) {
-		size->data.length.value =
-			FMUL(size->data.length.value, parent_size->value);
-
-		if (size->data.length.unit == CSS_UNIT_EX) {
-			size->data.length.value = FMUL(size->data.length.value,
-					FLTTOFIX(0.6));
-		}
-
-		size->data.length.unit = parent_size->unit;
-	} else if (size->data.length.unit == CSS_UNIT_PCT) {
-		size->data.length.value = FDIV(FMUL(size->data.length.value,
-				parent_size->value), FLTTOFIX(100));
-		size->data.length.unit = parent_size->unit;
-	}
-
-	size->status = CSS_FONT_SIZE_DIMENSION;
-
-	return CSS_OK;
-}
-
 static css_error set_libcss_node_data(void *pw, void *n,
 		void *libcss_node_data)
 {