Create Pepper-based CDM for EME WD (Blink changes)

Source/web/MediaKeysClientImpl.cpp

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "config.h"
+#include "MediaKeysClientImpl.h"
+
+#include "WebFrameClient.h"
+#include "WebFrameImpl.h"
+#include "core/dom/Document.h"
+#include "core/dom/ExecutionContext.h"
+#include "public/platform/WebContentDecryptionModule.h"
+
+using namespace WebCore;
+
+namespace blink {
+
+MediaKeysClientImpl::MediaKeysClientImpl()
+{
+}
+
+PassOwnPtr<WebContentDecryptionModule> MediaKeysClientImpl::createContentDecryptionModule(WebCore::ExecutionContext* executionContext, const String& keySystem)
+{
+    Document* document = toDocument(executionContext);
+    WebFrameImpl* webFrame = WebFrameImpl::fromFrame(document->frame());

[eseidel, 2014/03/21 17:48:04]

Hopefully this is never called on a detached document. :)

var detachedDocument = iframe.contentDocument;
iframe.src = "newthing";
detachedDocument.createContentDescriptionModule(); // boom!  document->frame()
is null!

+    WebSecurityOrigin securityOrigin(executionContext->securityOrigin());
+    return adoptPtr(webFrame->client()->createContentDecryptionModule(webFrame, securityOrigin, keySystem));
+}
+
+} // namespace blink