[webcrypto] Match the error handling defined by the spec.

Source/modules/crypto/CryptoResultImpl.cpp

 /*
  * Copyright (C) 2013 Google Inc. 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.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 27 matching lines @@
 #include "modules/crypto/NormalizeAlgorithm.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebArrayBuffer.h"
 #include "public/platform/WebCryptoAlgorithm.h"
 #include "wtf/ArrayBufferView.h"
 
 namespace WebCore {
 
 CryptoResultImpl::~CryptoResultImpl()
 {
-    ASSERT(m_finished);
-    ASSERT(!m_promiseResolver.get());
-    ASSERT(!m_requestState.isValid());
 }
 
 PassRefPtr<CryptoResultImpl> CryptoResultImpl::create(ScriptPromise promise)
 {
     return adoptRef(new CryptoResultImpl(activeExecutionContext(), promise));
 }
 
-void CryptoResultImpl::completeWithError()
+void CryptoResultImpl::completeWithError(const blink::WebString& errorDetails)
 {
     ASSERT(!m_finished);
 
     if (canCompletePromise()) {
         DOMRequestState::Scope scope(m_requestState);
+        if (!errorDetails.isEmpty()) {
+            // FIXME: Include the line number which started the crypto operation.
+            executionContext()->addConsoleMessage(JSMessageSource, ErrorMessageLevel, errorDetails);
+        }
         m_promiseResolver->reject(ScriptValue::createNull());
     }
+}
 
-    finish();
+void CryptoResultImpl::completeWithError()
+{
+    completeWithError(blink::WebString());
 }
 
 void CryptoResultImpl::completeWithBuffer(const blink::WebArrayBuffer& buffer)
 {
     ASSERT(!m_finished);
 
     if (canCompletePromise()) {
         DOMRequestState::Scope scope(m_requestState);
         m_promiseResolver->resolve(PassRefPtr<ArrayBuffer>(buffer));
     }
@@ skipping 78 matching lines @@
 }
 
 bool CryptoResultImpl::canCompletePromise() const
 {
     CheckValidThread();
     ExecutionContext* context = executionContext();
     return context && !context->activeDOMObjectsAreSuspended() && !context->activeDOMObjectsAreStopped();
 }
 
 } // namespace WebCore