Combine two validUnit calls

LayoutTests/css3/calc/calc-numbers.html

Index: LayoutTests/css3/calc/calc-numbers.html
diff --git a/LayoutTests/css3/calc/calc-numbers.html b/LayoutTests/css3/calc/calc-numbers.html
index 587becd5e86ab90dce8258a80def175422861b7f..1bb61ed0e42635fdb3b3e2885a3a17c60e98585f 100644
--- a/LayoutTests/css3/calc/calc-numbers.html
+++ b/LayoutTests/css3/calc/calc-numbers.html
@@ -18,12 +18,17 @@
     opacity: 0.9;
     opacity: calc((2 / 4) * 1px);
 }
+.num-length-invalid {
+    tab-size: 12345;
+    tab-size: calc(1 + 1px);
+}
 </style>
 <div class="default int"></div>
 <div class="default int-non-neg-invalid"></div>
 <div class="default float"></div>
 <div class="default float-invalid"></div>
 <div class="default px-invalid"></div>
+<div class="default num-length-invalid"></div>
 <script src="../../resources/js-test.js"></script>
 <script>
 if (window.testRunner)
@@ -38,4 +43,5 @@ shouldBe('getComputedValue(".int-non-neg-invalid", "tabSize")', '"12345"');
 shouldBeCloseTo('Number(getComputedValue(".float", "opacity"))', 0.5, .0001);
 shouldBe('getComputedValue(".float-invalid", "tabSize")', '"12345"');
 shouldBeCloseTo('Number(getComputedValue(".px-invalid", "opacity"))', 0.9, .0001);
+shouldBe('getComputedValue(".num-length-invalid", "tabSize")', '"12345"');
 </script>