[CSS Shapes] CSS parser accepts trailing position arguments

LayoutTests/fast/shapes/parsing/parsing-test-utils.js

 // Valid values for both shape-inside and shape-outside. Two values are specified when the shape property value
 // differs from the specified value. Three values are specified when the computed shape property value differs
 // from the specified value.
 // eg: "specified value/CSS Text value/computed style value"
 // or: ["specified value", "CSS Text value/computed style value"]
 // or: ["specified value", "CSS Text value", "Computed style value"]
 var validShapeValues = [
     "none",
     ["rectangle(10px, 20px, 30px, 40px)", "rectangle(10px, 20px, 30px, 40px)", "rectangle(10px, 20px, 30px, 40px, 0px, 0px)"],
     ["rectangle(10px, 20px, 30px, 40px, 5px)", "rectangle(10px, 20px, 30px, 40px, 5px)", "rectangle(10px, 20px, 30px, 40px, 5px, 5px)"],
@@ skipping 125 matching lines @@
     "circle(10px, 20px, 30px, 40px)", // FIXME: Remove this test once we do not support the deprecated CSS Shapes syntax anymore.
 
     "circle(10px 20px)",
     "circle(10px at 10px 10px 10px)",
     "circle(10px at 10px 10px at center)",
     "circle(10px at center center 10px)",
     "circle(at 10px 10px 10px)",
     "circle(at 10px 10px at center)",
     "circle(at center center 10px)",
 
+    "circle(at 10px 10px closest-side)",
+
     "ellipse(10px, 20px)", // FIXME: Remove this test once we do not support the deprecated CSS Shapes syntax anymore.
     "ellipse(10px, 20px, 30px)", // FIXME: Remove this test once we do not support the deprecated CSS Shapes syntax anymore.
     "ellipse(10px 20px 30px 40px)", // FIXME: Remove this test once we do not support the deprecated CSS Shapes syntax anymore.
 
     "ellipse(10px 20px 30px)",
     "ellipse(10px at 10px 10px 10px)",
     "ellipse(10px at 10px 10px at center)",
     "ellipse(10px at center center 10px)",
     "ellipse(10px 20px 30px at center center 10px)",
     "ellipse(at 10px 10px 10px)",
@@ skipping 123 matching lines @@
 
 function testNotInheritedShapeProperty(property, parentValue, childValue, expectedValue)
 {
     shouldBeEqualToString('getParentAndChildComputedStylesString("' + property + '", "' + parentValue + '", "' + childValue + '")', expectedValue);
 }
 
 function applyToEachArglist(testFunction, arglists)
 {
     arglists.forEach(function(arglist, i, a) {testFunction.apply(null, arglist);});
 }