[WebCrypto] Move LayoutTests from crypto to crypto/subtle

LayoutTests/crypto/resources/worker-infinite-loop-generateKey.js

-importScripts('common.js');
-
-function continuouslyGenerateRsaKey()
-{
-    var extractable = false;
-    var usages = ['sign', 'verify'];
-    // Note that the modulus length is small.
-    var algorithm = {name: "RSASSA-PKCS1-v1_5", modulusLength: 512, publicExponent: hexStringToUint8Array("010001"), hash: {name: 'sha-1'}};
-
-    return crypto.subtle.generateKey(algorithm, extractable, usages).then(function(result) {
-        // Infinite recursion intentional!
-        return continuouslyGenerateRsaKey();
-    });
-}
-
-// Starts a Promise which continually generates new RSA keys.
-var unusedPromise = continuouslyGenerateRsaKey();
-
-// Inform the outer script that the worker started.
-postMessage("Worker started");