[webcrypto] Require importKey() for JWK to provide data as a Javascript object rather than a JSON a…

LayoutTests/crypto/rsa-export-private-key.html

Index: LayoutTests/crypto/rsa-export-private-key.html
diff --git a/LayoutTests/crypto/rsa-export-private-key.html b/LayoutTests/crypto/rsa-export-private-key.html
index 574b69dfc9a8c8788c83162c34a93cd0dc49e423..ee8af2a5f02b3442969fb1a3f2632891ec9bb993 100644
--- a/LayoutTests/crypto/rsa-export-private-key.html
+++ b/LayoutTests/crypto/rsa-export-private-key.html
@@ -30,10 +30,9 @@ var privateKeyJSON = {
     "alg":"RS256",
     "kid":"2011-04-29"
 }
-var jwkKeyAsArrayBuffer = asciiToUint8Array(JSON.stringify(privateKeyJSON));
 
 debug("\nImporting a JWK key...");
-crypto.subtle.importKey("jwk", jwkKeyAsArrayBuffer, {name: "RSASSA-PKCS1-v1_5", hash: {name: "sha-256"}}, extractable, ['sign']).then(function(result) {
+crypto.subtle.importKey("jwk", privateKeyJSON, {name: "RSASSA-PKCS1-v1_5", hash: {name: "sha-256"}}, extractable, ['sign']).then(function(result) {
     key = result;
 
     debug("\nExporting the key as JWK...");