Change EME WebIDL to use ArrayBuffer/ArrayBufferView.

LayoutTests/media/encrypted-media/encrypted-media-utils.js

 var console = null;
 
 function consoleWrite(text)
 {
     if (!console && document.body) {
         console = document.createElement('div');
         document.body.appendChild(console);
     }
     var span = document.createElement('span');
     span.appendChild(document.createTextNode(text));
@@ skipping 67 matching lines @@
 // http://tools.ietf.org/html/draft-ietf-jose-json-web-key
 
 // Encodes data into base64 string without trailing '='.
 function base64Encode(data)
 {
     var result = btoa(String.fromCharCode.apply(null, data));
     return result.replace(/=+$/g, '');
 }
 
 // Creates a JWK from raw key ID and key.
+// |keyId| and |key| are expected to be ArrayBufferViews, not base64-encoded.
 function createJWK(keyId, key)
 {
     var jwk = '{"kty":"oct","kid":"';
+    // FIXME: Should use base64URLEncoding.
     jwk += base64Encode(keyId);
     jwk += '","k":"';
     jwk += base64Encode(key);
     jwk += '"}';
     return jwk;
 }
 
 // Creates a JWK Set from multiple JWKs.
 function createJWKSet()
 {
@@ skipping 13 matching lines @@
     // currently no way to report a failed test in the test harness, errors
     // are reported using force_timeout().
     if (message)
         consoleWrite(message + ': ' + error.message);
     else if (error)
         consoleWrite(error.message);
 
     test.force_timeout();
     test.done();
 }