Auto merge of #13681 - gpoesia:master, r=mbrubeck

Fix margin size calculation for TableWrapper

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Fixes inline size calculation for TableWrapper. The table's width was always reaching the inline size equation solver as a specified variable, which was causing the system to be overdetermined when there was a margin specified for the table, and this caused the overflow reported in #12748. The fix consists in handling three cases when the table's width is not specified: if the preferred size of all columns fits, it is returned; if the minimum size does not fit, it is returned instead (it will overflow), otherwise, it is returned as a free variable (that should be solved together with the margin to some value above the minimum width and below the preferred width).

---
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #12748
- [X] There are tests for these changes

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tests/wpt/mozilla/meta/MANIFEST.json

@@ -5220,6 +5220,18 @@
             "url": "/_mozilla/css/table_intrinsic_style_specified_width_a.html"
           }
         ],
+        "css/table_margin_a.html": [
+          {
+            "path": "css/table_margin_a.html",
+            "references": [
+              [
+                "/_mozilla/css/table_margin_ref.html",
+                "=="
+              ]
+            ],
+            "url": "/_mozilla/css/table_margin_a.html"
+          }
+        ],
         "css/table_margin_auto_a.html": [
           {
             "path": "css/table_margin_auto_a.html",
@@ -20586,6 +20598,18 @@
           "url": "/_mozilla/css/table_intrinsic_style_specified_width_a.html"
         }
       ],
+      "css/table_margin_a.html": [
+        {
+          "path": "css/table_margin_a.html",
+          "references": [
+            [
+              "/_mozilla/css/table_margin_ref.html",
+              "=="
+            ]
+          ],
+          "url": "/_mozilla/css/table_margin_a.html"
+        }
+      ],
       "css/table_margin_auto_a.html": [
         {
           "path": "css/table_margin_auto_a.html",