layout: Add initial support for row height distribution

This change adds a version of row height distribution that follows the
distribtuion algorithm used for tables in Blink's LayoutNG. This is just
an intermediate step toward implementing a distribution algorithm for
both rows and columns more similar to Layout NG.

The CSS Table 3 specification is often wrong with regard to web
compatability, which is why we have abandoned it in favor of the Layout
NG algorithm for row height distribution.  this work.

Co-authored-by: Oriol Brufau <obrufau@igalia.com>

components/layout_2020/sizing.rs

@@ -24,13 +24,6 @@ pub(crate) struct ContentSizes {
 
 /// <https://drafts.csswg.org/css-sizing/#intrinsic-sizes>
 impl ContentSizes {
-    pub fn zero() -> Self {
-        Self {
-            min_content: Au::zero(),
-            max_content: Au::zero(),
-        }
-    }
-
     pub fn map(&self, f: impl Fn(Au) -> Au) -> Self {
         Self {
             min_content: f(self.min_content),
@@ -57,6 +50,19 @@ impl ContentSizes {
     }
 }
 
+impl Zero for ContentSizes {
+    fn zero() -> Self {
+        Self {
+            min_content: Au::zero(),
+            max_content: Au::zero(),
+        }
+    }
+
+    fn is_zero(&self) -> bool {
+        self.min_content.is_zero() && self.max_content.is_zero()
+    }
+}
+
 impl Add for ContentSizes {
     type Output = Self;
 

tests/wpt/meta/css/css-tables/column-track-merging.html.ini

@@ -2,9 +2,6 @@
   [main table 1]
     expected: FAIL
 
-  [main table 2]
-    expected: FAIL
-
   [main table 4]
     expected: FAIL
 
@@ -31,3 +28,6 @@
 
   [main table 3]
     expected: FAIL
+
+  [main table 2]
+    expected: FAIL

tests/wpt/meta/css/css-tables/height-distribution/computing-row-measure-0.html.ini

@@ -1,10 +1,4 @@
 [computing-row-measure-0.html]
-  [Checking intermediate min-content height for span 1 (1)]
-    expected: FAIL
-
-  [Checking intermediate min-content height for span 1 (3)]
-    expected: FAIL
-
   [Checking intermediate min-content height for span 1 (2)]
     expected: FAIL
 

tests/wpt/meta/css/css-tables/height-distribution/computing-row-measure-1.html.ini

@@ -1,9 +1,9 @@
 [computing-row-measure-1.html]
-  [Checking intermediate min-content width for span 2 (1)]
+  [Checking intermediate min-content width for span 2 (4)]
     expected: FAIL
 
-  [Checking intermediate min-content width for span 2 (2)]
+  [Checking intermediate min-content width for span 2 (1)]
     expected: FAIL
 
-  [Checking intermediate min-content width for span 2 (4)]
+  [Checking intermediate min-content width for span 2 (2)]
     expected: FAIL

tests/wpt/meta/css/css-tables/html5-table-formatting-2.html.ini

@@ -11,26 +11,14 @@
   [Border-spacing is added between any two unmerged columns (2)]
     expected: FAIL
 
-  [Border-spacing is added between any two unmerged rows (2)]
-    expected: FAIL
-
   [Border-spacing is added between any two unmerged columns (3)]
     expected: FAIL
 
-  [Border-spacing is added between any two unmerged rows (3)]
-    expected: FAIL
-
   [Border-spacing is added between any two unmerged columns (4)]
     expected: FAIL
 
-  [Border-spacing is added between any two unmerged rows (4)]
-    expected: FAIL
-
   [Border-spacing is added between any two unmerged columns (5)]
     expected: FAIL
 
-  [Border-spacing is added between any two unmerged rows (5)]
-    expected: FAIL
-
   [Explicitely defined rows are not merged]
     expected: FAIL

tests/wpt/meta/css/css-tables/table-model-fixup.html.ini

@@ -2,9 +2,6 @@
   [2.1. An anonymous table-row box must be generated around each sequence of consecutive children of a table-root box which are not proper table child boxes. (1/2)]
     expected: FAIL
 
-  [2.1. An anonymous table-row box must be generated around each sequence of consecutive children of a table-root box which are not proper table child boxes. (2/2)]
-    expected: FAIL
-
   [2.2. An anonymous table-row box must be generated around each sequence of consecutive children of a table-row-grouping box which are not table-row boxes. (1/3)]
     expected: FAIL
 

tests/wpt/meta/css/css-tables/tentative/baseline-td.html.ini

@@ -2,14 +2,5 @@
   [table, .display-table 1]
     expected: FAIL
 
-  [table, .display-table 2]
-    expected: FAIL
-
   [table, .display-table 3]
     expected: FAIL
-
-  [table, .display-table 4]
-    expected: FAIL
-
-  [table, .display-table 5]
-    expected: FAIL

tests/wpt/meta/css/css-tables/tentative/colspan-redistribution.html.ini

@@ -14,9 +14,6 @@
   [table 6]
     expected: FAIL
 
-  [table 7]
-    expected: FAIL
-
   [table 9]
     expected: FAIL
 
@@ -85,3 +82,6 @@
 
   [table 8]
     expected: FAIL
+
+  [table 7]
+    expected: FAIL

tests/wpt/meta/css/css-tables/tentative/rowspan-height-redistribution.html.ini

@@ -1,4 +1,16 @@
 [rowspan-height-redistribution.html]
+  [table 7]
+    expected: FAIL
+
+  [table 8]
+    expected: FAIL
+
+  [table 22]
+    expected: FAIL
+
+  [table 23]
+    expected: FAIL
+
   [table 2]
     expected: FAIL
 
@@ -14,13 +26,19 @@
   [table 6]
     expected: FAIL
 
-  [table 7]
+  [table 9]
     expected: FAIL
 
-  [table 8]
+  [table 10]
     expected: FAIL
 
-  [table 9]
+  [table 11]
+    expected: FAIL
+
+  [table 12]
+    expected: FAIL
+
+  [table 13]
     expected: FAIL
 
   [table 14]
@@ -29,23 +47,20 @@
   [table 15]
     expected: FAIL
 
+  [table 16]
+    expected: FAIL
+
   [table 17]
     expected: FAIL
 
   [table 18]
     expected: FAIL
 
-  [table 19]
+  [table 20]
     expected: FAIL
 
   [table 21]
     expected: FAIL
 
-  [table 22]
-    expected: FAIL
-
-  [table 23]
-    expected: FAIL
-
-  [table 20]
+  [table 24]
     expected: FAIL

tests/wpt/meta/css/css-tables/tentative/table-height-redistribution.html.ini

@@ -56,9 +56,6 @@
   [table 23]
     expected: FAIL
 
-  [table 24]
-    expected: FAIL
-
   [table 25]
     expected: FAIL
 

tests/wpt/meta/css/css-tables/tentative/table-width-redistribution-fixed-padding.html.ini

@@ -14,9 +14,6 @@
   [table 6]
     expected: FAIL
 
-  [table 7]
-    expected: FAIL
-
   [table 9]
     expected: FAIL
 
@@ -37,3 +34,6 @@
 
   [table 15]
     expected: FAIL
+
+  [table 7]
+    expected: FAIL

tests/wpt/meta/css/css-tables/tentative/table-width-redistribution-fixed.html.ini

@@ -26,9 +26,6 @@
   [table 11]
     expected: FAIL
 
-  [table 12]
-    expected: FAIL
-
   [table 14]
     expected: FAIL
 
@@ -58,3 +55,6 @@
 
   [table 26]
     expected: FAIL
+
+  [table 12]
+    expected: FAIL

tests/wpt/meta/css/css-tables/tentative/tbody-height-redistribution.html.ini

@@ -14,9 +14,6 @@
   [table 5]
     expected: FAIL
 
-  [table 6]
-    expected: FAIL
-
   [table 7]
     expected: FAIL
 

tests/wpt/meta/css/css-tables/tentative/td-box-sizing-001.html.ini

@@ -11,9 +11,6 @@
   [table 6]
     expected: FAIL
 
-  [table 7]
-    expected: FAIL
-
   [table 8]
     expected: FAIL