Remove use of WebCrypto digestSynchronous in Blink.

Source/modules/websockets/WebSocketHandshake.cpp

 /*
  * Copyright (C) 2011 Google Inc.  All rights reserved.
  * Copyright (C) Research In Motion Limited 2011. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 108 matching lines @@
 String WebSocketHandshake::getExpectedWebSocketAccept(const String& secWebSocketKey)
 {
     static const char webSocketKeyGUID[] = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
     CString keyData = secWebSocketKey.ascii();
 
     StringBuilder digestable;
     digestable.append(secWebSocketKey);
     digestable.append(webSocketKeyGUID, strlen(webSocketKeyGUID));
     CString digestableCString = digestable.toString().utf8();
     DigestValue digest;
-    computeDigest(HashAlgorithmSha1, digestableCString.data(), digestableCString.length(), digest);
+    bool digestSuccess = computeDigest(HashAlgorithmSha1, digestableCString.data(), digestableCString.length(), digest);
+    RELEASE_ASSERT(digestSuccess);
 
     return base64Encode(reinterpret_cast<const char*>(digest.data()), sha1HashSize);
 }
 
 WebSocketHandshake::WebSocketHandshake(const KURL& url, const String& protocol, Document* document)
     : m_url(url)
     , m_clientProtocol(protocol)
     , m_secure(m_url.protocolIs("wss"))
     , m_document(document)
     , m_mode(Incomplete)
@@ skipping 422 matching lines @@
         }
         if (!match) {
             m_failureReason = formatHandshakeFailureReason("Sent non-empty 'Sec-WebSocket-Protocol' header but no response was received");
             return false;
         }
     }
     return true;
 }
 
 } // namespace WebCore