[webcrypto] Implement structured clone of keys (blink-side).

LayoutTests/crypto/resources/common.js

 // The following key pair is comprised of the SPKI (public key) and PKCS#8
 // (private key) representations of the key pair provided in Example 1 of the
 // NIST test vectors at ftp://ftp.rsa.com/pub/rsalabs/tmp/pkcs1v15sign-vectors.txt
 var kPublicKeySpkiDerHex = "30819f300d06092a864886f70d010101050003818d0030818902818100a56e4a0e701017589a5187dc7ea841d156f2ec0e36ad52a44dfeb1e61f7ad991d8c51056ffedb162b4c0f283a12a88a394dff526ab7291cbb307ceabfce0b1dfd5cd9508096d5b2b8b6df5d671ef6377c0921cb23c270a70e2598e6ff89d19f105acc2d3f0cb35f29280e1386b6f64c4ef22e1e1f20d0ce8cffb2249bd9a21370203010001";
 var kPrivateKeyPkcs8DerHex = "30820275020100300d06092a864886f70d01010105000482025f3082025b02010002818100a56e4a0e701017589a5187dc7ea841d156f2ec0e36ad52a44dfeb1e61f7ad991d8c51056ffedb162b4c0f283a12a88a394dff526ab7291cbb307ceabfce0b1dfd5cd9508096d5b2b8b6df5d671ef6377c0921cb23c270a70e2598e6ff89d19f105acc2d3f0cb35f29280e1386b6f64c4ef22e1e1f20d0ce8cffb2249bd9a2137020301000102818033a5042a90b27d4f5451" +
                              "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";
 
 function importTestKeys()
 {
     var data = asciiToUint8Array("16 bytes of key!");
@@ skipping 140 matching lines @@
         debug("PASS: '" + code + "' accepted with " + result);
     }
 
     function rejectCallback(result)
     {
         debug("FAIL: '" + code + "' rejected with " + result);
     }
 
     addTask(promise.then(acceptCallback, rejectCallback));
 }
+
+// Returns a Promise for the cloned key.
+function cloneKey(key)
+{
+    // Sending an object through a MessagePort implicitly clones it.
+    // Use a single MessageChannel so requests complete in FIFO order.
+    var self = cloneKey;
+    if (!self.channel) {
+        self.channel = new MessageChannel();
+        self.callbacks = [];
+        self.channel.port1.addEventListener('message', function(e) {
+            var callback = self.callbacks.shift();
+            callback(e.data);
+        }, false);
+        self.channel.port1.start();
+    }
+
+    return new Promise(function(resolve, reject) {
+        self.callbacks.push(resolve);
+        self.channel.port2.postMessage(key);
+    });
+}
+
+// Logging the serialized format ensures that if it changes it will break tests.
+function logSerializedKey(o)
+{
+    if (internals)
+        debug("Serialized key bytes: " + bytesToHexString(internals.serializeObject(o)));
+}
+
+function shouldEvaluateAs(actual, expectedValue)
+{
+    if (typeof expectedValue == "string")
+        return shouldBeEqualToString(actual, expectedValue);
+    return shouldEvaluateTo(actual, expectedValue);
+}