[CSS Grid Layout] Small refactoring in grid-auto-flow-get-set.html test

LayoutTests/fast/css-grid-layout/resources/grid-definitions-parsing-utils.js

Index: LayoutTests/fast/css-grid-layout/resources/grid-definitions-parsing-utils.js
diff --git a/LayoutTests/fast/css-grid-layout/resources/grid-definitions-parsing-utils.js b/LayoutTests/fast/css-grid-layout/resources/grid-definitions-parsing-utils.js
index ca22800a8238f2fd6582717f2418b9deab6c9b06..edbcd7c8a331102046623de503cb824b4579d0d0 100644
--- a/LayoutTests/fast/css-grid-layout/resources/grid-definitions-parsing-utils.js
+++ b/LayoutTests/fast/css-grid-layout/resources/grid-definitions-parsing-utils.js
@@ -44,4 +44,20 @@ function testGridDefinitionsSetBadJSValues(columnValue, rowValue)
     // We can't use testSetJSValues as element.style.gridTemplateRows returns "".
     testGridDefinitionsValues(element, "none", "none");
     document.body.removeChild(element);
-}
+}
+
+function checkGridAutoFlowSetCSSValue(elementId, expectedValue)
+{
+    shouldBe("window.getComputedStyle(" + elementId + ", '').getPropertyValue('grid-auto-flow')", "'" + expectedValue + "'");
+}
+
+function checkGridAutoFlowSetJSValue(newValue, expectedStyleValue, expectedComputedStyleValue)
+{
+    element = document.createElement("div");
+    document.body.appendChild(element);
+    if (newValue)
+        element.style.gridAutoFlow = newValue;
+    shouldBe("element.style.gridAutoFlow", "'" + expectedStyleValue + "'");
+    shouldBe("window.getComputedStyle(element, '').getPropertyValue('grid-auto-flow')", "'" + expectedComputedStyleValue + "'");
+    document.body.removeChild(element);
+}