layout: Fix logic for transforms with non-invertible matrix (#37147)

When the the current transformation matrix of a box isn't invertible,
the box and its content shouldn't be displayed.

However, the logic was broken:
- It was only checking the `transform` property, but not individual
transform properties like `scale`.
- It was treating matrices with m₁₁=0 or m₂₂=0 and non-invertible, even
when they can still be invertible and have a visible outcome.
- When m₁₁=0 or m₂₂=0 weren't caused by `transform`, it was replacing
the matrix with the identity.

Testing: Adding new WPT
Fixes: #37146

Signed-off-by: Oriol Brufau <obrufau@igalia.com>

tests/wpt/meta/MANIFEST.json

@@ -279684,6 +279684,19 @@
         {}
        ]
       ],
+      "individual-transform-3.html": [
+       "2c81cb12156134ee8deca6abf0043848ac8bc750",
+       [
+        null,
+        [
+         [
+          "/css/reference/ref-filled-green-200px-square.html",
+          "=="
+         ]
+        ],
+        {}
+       ]
+      ],
       "stacking-context-001.html": [
        "1a754c5d70b607396ffe2db1d04f2294aeca1041",
        [
@@ -284738,6 +284751,19 @@
        {}
       ]
      ],
+     "transform-matrix-009.html": [
+      "81f04db0d103202180aba2625205643c376483af",
+      [
+       null,
+       [
+        [
+         "/css/reference/ref-filled-green-200px-square.html",
+         "=="
+        ]
+       ],
+       {}
+      ]
+     ],
      "transform-origin": {
       "svg-origin-length-001.html": [
        "2f2256361cadd4f69aa08fd775a4305219a41fdd",