Auto merge of #12370 - emilio:wrap, r=mbrubeck

Fix line-breaking with white-space: pre-wrap/pre-line;

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Not sure if this is the appropriate fix, but we'll know soon.

---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #12369

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- [x] There are tests for these changes OR

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r? @mbrubeck

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tests/wpt/mozilla/meta/MANIFEST.json

@@ -6150,6 +6150,18 @@
             "url": "/_mozilla/css/test_variable_serialization_specified.html"
           }
         ],
+        "css/white-space-pre-line-long-line.html": [
+          {
+            "path": "css/white-space-pre-line-long-line.html",
+            "url": "/_mozilla/css/white-space-pre-line-long-line.html"
+          }
+        ],
+        "css/white-space-pre-wrap-long-line.html": [
+          {
+            "path": "css/white-space-pre-wrap-long-line.html",
+            "url": "/_mozilla/css/white-space-pre-wrap-long-line.html"
+          }
+        ],
         "mozilla/DOMParser.html": [
           {
             "path": "mozilla/DOMParser.html",