Auto merge of #7082 - servo:linux-fail, r=metajack

Mark some tests as failing on Linux, not just Ubuntu 14.04.

They also fail for me on Archlinux.

(`absolute-replaced-height-007.htm` is disabled anyway, but let’s change it as well for consistency.)

r? @larsbergstrom

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tests/wpt/metadata-css/css21_dev/html4/absolute-replaced-height-007.htm.ini

@@ -2,4 +2,4 @@
   type: reftest
   disabled: unstable
   expected:
-    if (os == "linux") and (version == "Ubuntu 14.04"): FAIL
+    if (os == "linux"): FAIL

tests/wpt/metadata-css/css21_dev/html4/font-size-zero-1.htm.ini

@@ -1,4 +1,4 @@
 [font-size-zero-1.htm]
   type: reftest
   expected:
-    if (os == "linux") and (version == "Ubuntu 14.04"): FAIL
+    if (os == "linux"): FAIL

tests/wpt/metadata-css/css21_dev/html4/font-size-zero-2.htm.ini

@@ -1,4 +1,4 @@
 [font-size-zero-2.htm]
   type: reftest
   expected:
-    if (os == "linux") and (version == "Ubuntu 14.04"): FAIL
+    if (os == "linux"): FAIL