WebCrypto: Add interface for exportKey().

LayoutTests/crypto/resources/common.js

Index: LayoutTests/crypto/resources/common.js
diff --git a/LayoutTests/crypto/resources/common.js b/LayoutTests/crypto/resources/common.js
index c208412acd64d2d1a07726d65832210321b2370e..a8e2e300a92d8ea5ce448b1e258ed371dd210759 100644
--- a/LayoutTests/crypto/resources/common.js
+++ b/LayoutTests/crypto/resources/common.js
@@ -2,13 +2,13 @@ function importTestKeys()
 {
     var keyFormat = "spki";
     var data = new Uint8Array([]);
-    var extractable = false;
+    var extractable = true;
     var keyUsages = ['encrypt', 'decrypt', 'sign', 'verify'];
 
     var hmacPromise = crypto.subtle.importKey(keyFormat, data, {name: 'hmac', hash: {name: 'sha-1'}}, extractable, keyUsages);
     var rsaSsaPromise = crypto.subtle.importKey(keyFormat, data, {name: 'RSASSA-PKCS1-v1_5', hash: {name: 'sha-1'}}, extractable, keyUsages);
     var aesCbcPromise = crypto.subtle.importKey(keyFormat, data, {name: 'AES-CBC'}, extractable, keyUsages);
-    var aesCbcJustDecrypt = crypto.subtle.importKey(keyFormat, data, {name: 'AES-CBC'}, extractable, ['decrypt']);
+    var aesCbcJustDecrypt = crypto.subtle.importKey(keyFormat, data, {name: 'AES-CBC'}, false, ['decrypt']);
 
     return Promise.every(hmacPromise, rsaSsaPromise, aesCbcPromise, aesCbcJustDecrypt).then(function(results) {
         return {