Fix typo in simple-polygon.js LayoutTest helper

LayoutTests/fast/shapes/resources/simple-polygon.js

Index: LayoutTests/fast/shapes/resources/simple-polygon.js
diff --git a/LayoutTests/fast/shapes/resources/simple-polygon.js b/LayoutTests/fast/shapes/resources/simple-polygon.js
index 1b69e075d8061954fe7445ca989cadb7a5fffcf6..7343309a1a6206d6f4e0c8265bc2704faa0d9f6d 100644
--- a/LayoutTests/fast/shapes/resources/simple-polygon.js
+++ b/LayoutTests/fast/shapes/resources/simple-polygon.js
@@ -106,7 +106,7 @@ function polygonLineIntercepts(polygon, y, lineHeight) {
 // with the the polygon's bounds minimum Y value, and each line of characters fills the interior
 // of the polygon.
 
-function generatePolygonContentString(polygon, lineheight) {
+function generatePolygonContentString(polygon, lineHeight) {
     var result = "";
 
     for (var y = polygon.minY; y < polygon.maxY; y += lineHeight) {