Set proper referrer for css resource fetching

LayoutTests/http/tests/css/resources/referrer-check.php

+<?php
+
+function getReferrerPath() {
+    if (!isset($_SERVER["HTTP_REFERER"]))
+        return "";
+    $url = parse_url($_SERVER["HTTP_REFERER"]);
+    return $url['path'];
+}
+
+function putImage() {
+    $image = "../../resources/square100.png";
+    header("Content-Type: image/png");
+    header("Content-Length: " . filesize($image));
+    ob_clean();
+    flush();
+    readfile($image);
+}
+
+function putFont() {
+    $font = "../../../../resources/Ahem.ttf";
+    header("Content-Type: font/truetype");
+    header("Content-Length: " . filesize($font));
+    ob_clean();
+    flush();
+    readfile($font);
+}
+
+$expectedReferrerPaths = array(
+    "document" => "/css/css-resources-referrer.html",
+    "sheet" => "/css/resources/css-resources-referrer.css",
+    "importedSheet" => "/css/resources/css-resources-referrer-import.css"
+);
+
+$from = $_GET["from"];
+$resource = $_GET["resource"];
+$referrerPath = getReferrerPath();
+
+if ($referrerPath === $expectedReferrerPaths[$from]) {
+    if ($resource === "image" || $resource === "image2")
+        putImage();
+    else if ($resource === "font")
+        putFont();
+    else
+        header("HTTP/1.1 500 Internal Server Error");
+} else {
+    header("HTTP/1.1 500 Internal Server Error");
+}
+
+?>